diff --git a/src/kaggle/api/kaggle_api_extended.py b/src/kaggle/api/kaggle_api_extended.py
index 5c5d449..edd95ea 100644
--- a/src/kaggle/api/kaggle_api_extended.py
+++ b/src/kaggle/api/kaggle_api_extended.py
@@ -19,9 +19,11 @@
 
 import csv
 from datetime import datetime
+from enum import Enum
 import io
 
 import json  # Needed by mypy.
+import logging
 import os
 
 import re  # Needed by mypy.
@@ -48,7 +50,7 @@
 from google.protobuf import field_mask_pb2
 
 import kaggle
-from kagglesdk import KaggleClient, KaggleEnv  # type: ignore[attr-defined]
+from kagglesdk import get_access_token_from_env, KaggleClient, KaggleEnv  # type: ignore[attr-defined]
 from kagglesdk.admin.types.inbox_file_service import CreateInboxFileRequest
 from kagglesdk.blobs.types.blob_api_service import ApiStartBlobUploadRequest, ApiStartBlobUploadResponse, ApiBlobType
 from kagglesdk.competitions.types.competition_api_service import (
@@ -150,6 +152,14 @@
 T = TypeVar('T')
 
 
+class AuthMethod(Enum):
+    LEGACY_API_KEY = 0
+    ACCESS_TOKEN = 1
+
+    def __str__(self):
+        return self.name
+
+
 class DirectoryArchive(object):
 
     def __init__(self, fullpath, fmt):
@@ -365,7 +375,9 @@ class KaggleApi:
     CONFIG_NAME_COMPETITION = 'competition'
     CONFIG_NAME_PATH = 'path'
     CONFIG_NAME_USER = 'username'
+    CONFIG_NAME_AUTH_METHOD = 'auth_method'
     CONFIG_NAME_KEY = 'key'
+    CONFIG_NAME_TOKEN = 'token'
     CONFIG_NAME_SSL_CA_CERT = 'ssl_ca_cert'
 
     HEADER_API_VERSION = 'X-Kaggle-ApiVersion'
@@ -398,10 +410,12 @@ class KaggleApi:
 
     args: List[str] = []
     if os.environ.get('KAGGLE_API_ENVIRONMENT') == 'LOCALHOST':
-        # Make it verbose when running in the debugger.
-        args = ['--verbose', '--local']
-    elif os.environ.get('KAGGLE_API_ENDPOINT') == 'http://localhost':
-        args = ['--local']
+        args.append('--local')
+    verbose = (os.environ.get('VERBOSE') or os.environ.get('VERBOSE_OUTPUT') or "false").lower()
+    if verbose in ('1', 'true', 'yes'):
+        args.append('--verbose')
+        logging.basicConfig(level=logging.DEBUG)
+    logger = logging.getLogger(__name__)
 
     # Kernels valid types
     valid_push_kernel_types = ['script', 'notebook']
@@ -513,39 +527,76 @@ def retriable_func(*args):
     ## Authentication
 
     def authenticate(self) -> None:
-        """Authenticate the user with the Kaggle API.
+        if self._authenticate_with_access_token():
+            return
+        if self._authenticate_with_legacy_apikey():
+            return
+        print(
+            'Could not find {}. Make sure it\'s located in'
+            ' {}. Or use the environment method. See setup'
+            ' instructions at'
+            ' https://github.com/Kaggle/kaggle-api/'.format(self.config_file, self.config_dir)
+        )
+        exit(1)
+
+    def _authenticate_with_legacy_apikey(self) -> bool:
+        """Authenticate the user with the Kaggle API using legacy API key.
 
         This method will generate a configuration, first checking the
         environment for credential variables, and falling back to looking
         for the .kaggle/kaggle.json configuration file.
         """
 
-        config_data: Dict[str, str] = {}
+        config_values: Dict[str, str] = {}
         # Ex: 'datasets list', 'competitions files', 'models instances get', etc.
         api_command = ' '.join(sys.argv[1:])
 
         # Step 1: try getting username/password from environment
-        config_data = self.read_config_environment(config_data)
+        config_values = self.read_config_environment(config_values)
 
         # Step 2: if credentials were not in env read in configuration file
-        if self.CONFIG_NAME_USER not in config_data or self.CONFIG_NAME_KEY not in config_data:
+        if self.CONFIG_NAME_USER not in config_values or self.CONFIG_NAME_KEY not in config_values:
             if os.path.exists(self.config):
-                config_data = self.read_config_file(config_data)
-            elif self._is_help_or_version_command(api_command) or (
-                len(sys.argv) > 2 and api_command.startswith(self.command_prefixes_allowing_anonymous_access)
-            ):
+                config_values = self.read_config_file(config_values)
+            elif self._command_allows_logged_out(api_command):
                 # Some API commands should be allowed without authentication.
-                return
+                return True
             else:
-                raise IOError(
-                    'Could not find {}. Make sure it\'s located in'
-                    ' {}. Or use the environment method. See setup'
-                    ' instructions at'
-                    ' https://github.com/Kaggle/kaggle-api/'.format(self.config_file, self.config_dir)
-                )
+                return False
+
+        # Step 3: Validate and save
+        # Username and password are required.
+        for item in [self.CONFIG_NAME_USER, self.CONFIG_NAME_KEY]:
+            if item not in config_values:
+                raise ValueError('Error: Missing %s in configuration.' % item)
+        self.config_values = config_values
+        self.config_values[self.CONFIG_NAME_AUTH_METHOD] = AuthMethod.LEGACY_API_KEY
+        self.logger.debug(f'Authenticated with legacy api key in: {self.config}')
+        return True
+
+    def _authenticate_with_access_token(self) -> bool:
+        (access_token, source) = get_access_token_from_env()
+        if not access_token:
+            return False
+
+        username = self._introspect_token(access_token)
+        if not username:
+            self.logger.debug(f'Ignoring invalid/expired access token in \"{source}\".')
+            return False
 
-        # Step 3: load into configuration!
-        self._load_config(config_data)
+        self.config_values: Dict[str, str] = {
+            self.CONFIG_NAME_TOKEN: access_token,
+            self.CONFIG_NAME_USER: username,
+            self.CONFIG_NAME_AUTH_METHOD: AuthMethod.ACCESS_TOKEN,
+        }
+        self.logger.debug(f'Authenticated with access token in: {source}')
+        return True
+
+    def _command_allows_logged_out(self, api_command: str) -> bool:
+        # Some API commands do not required authentication.
+        return self._is_help_or_version_command(api_command) or (
+            len(sys.argv) > 2 and api_command.startswith(self.command_prefixes_allowing_anonymous_access)
+        )
 
     def _is_help_or_version_command(self, api_command: str) -> bool:
         """Determines if the string command passed in is for a help or version
@@ -582,23 +633,6 @@ def read_config_environment(self, config_data: Optional[Dict[str, str]] = None)
 
     ## Configuration
 
-    def _load_config(self, config_data: Dict[str, str]) -> None:
-        """The final step of the authenticate steps, where we load the values from
-        config_data into the Configuration object.
-
-        Parameters
-        ==========
-        config_data: a dictionary with configuration values (keys) to read
-                     into self.config_values
-        """
-        # Username and password are required.
-
-        for item in [self.CONFIG_NAME_USER, self.CONFIG_NAME_KEY]:
-            if item not in config_data:
-                raise ValueError('Error: Missing %s in configuration.' % item)
-
-        self.config_values = config_data
-
     def read_config_file(self, config_data: Optional[Dict[str, str]] = None, quiet: bool = False) -> Dict[str, str]:
         """read_config_file is the first effort to get a username and key to
         authenticate to the Kaggle API. Since we can get the username and password
@@ -715,9 +749,7 @@ def get_config_value(self, name: str) -> Optional[str]:
         ==========
         name: the config value key to get
         """
-        if name in self.config_values:
-            return self.config_values[name]
-        return None
+        return self.config_values.get(name)
 
     def get_default_download_dir(self, *subdirs: str) -> str:
         """Get the download path for a file. If not defined, return default from
@@ -749,7 +781,7 @@ def print_config_value(self, name, prefix='- ', separator=': '):
         value_out = 'None'
         if name in self.config_values and self.config_values[name] is not None:
             value_out = self.config_values[name]
-        print(prefix + name + separator + value_out)
+        print(f"{prefix}{name}{separator}{value_out}")
 
     def print_config_values(self, prefix='- '):
         """Print all configuration values.
@@ -762,6 +794,7 @@ def print_config_values(self, prefix='- '):
             return
         print('Configuration values from ' + self.config_dir)
         self.print_config_value(self.CONFIG_NAME_USER, prefix=prefix)
+        self.print_config_value(self.CONFIG_NAME_AUTH_METHOD, prefix=prefix)
         self.print_config_value(self.CONFIG_NAME_PATH, prefix=prefix)
         self.print_config_value(self.CONFIG_NAME_PROXY, prefix=prefix)
         self.print_config_value(self.CONFIG_NAME_COMPETITION, prefix=prefix)
@@ -777,9 +810,12 @@ def build_kaggle_client(self) -> kagglesdk.kaggle_client.KaggleClient:
             )
         )
         verbose = '--verbose' in self.args or '-v' in self.args
-        #    config = self.api_client.configuration
         return KaggleClient(
-            env=env, verbose=verbose, username=self.config_values['username'], password=self.config_values['key']
+            env=env,
+            verbose=verbose,
+            username=self.config_values.get(self.CONFIG_NAME_USER),
+            password=self.config_values.get(self.CONFIG_NAME_KEY),
+            api_token=self.config_values.get(self.CONFIG_NAME_TOKEN),
         )
 
     def camel_to_snake(self, name: str) -> str:
diff --git a/src/kagglesdk/__init__.py b/src/kagglesdk/__init__.py
index a14cc66..1d6768f 100644
--- a/src/kagglesdk/__init__.py
+++ b/src/kagglesdk/__init__.py
@@ -1,2 +1,2 @@
 from kagglesdk.kaggle_client import KaggleClient
-from kagglesdk.kaggle_env import KaggleEnv
+from kagglesdk.kaggle_env import get_access_token_from_env, KaggleEnv
diff --git a/src/kagglesdk/kaggle_client.py b/src/kagglesdk/kaggle_client.py
index b375b6e..6cdb6ae 100644
--- a/src/kagglesdk/kaggle_client.py
+++ b/src/kagglesdk/kaggle_client.py
@@ -1,73 +1,74 @@
-from kagglesdk.kernels.services.kernels_api_service import KernelsApiClient
-from kagglesdk.blobs.services.blob_api_service import BlobApiClient
-from kagglesdk.education.services.education_api_service import EducationApiClient
+from kagglesdk.security.services.oauth_service import OAuthClient
 from kagglesdk.models.services.model_api_service import ModelApiClient
 from kagglesdk.models.services.model_service import ModelClient
+from kagglesdk.kernels.services.kernels_api_service import KernelsApiClient
 from kagglesdk.competitions.services.competition_api_service import CompetitionApiClient
+from kagglesdk.education.services.education_api_service import EducationApiClient
 from kagglesdk.datasets.services.dataset_api_service import DatasetApiClient
-from kagglesdk.admin.services.inbox_file_service import InboxFileClient
-from kagglesdk.security.services.oauth_service import OAuthClient
 from kagglesdk.users.services.account_service import AccountClient
+from kagglesdk.admin.services.inbox_file_service import InboxFileClient
+from kagglesdk.blobs.services.blob_api_service import BlobApiClient
 from kagglesdk.kaggle_env import KaggleEnv
 from kagglesdk.kaggle_http_client import KaggleHttpClient
 
 
 class KaggleClient(object):
-  class Kernels(object):
-    def __init__(self, http_client: KaggleHttpClient):
-      self.kernels_api_client = KernelsApiClient(http_client)
-
-  class Blobs(object):
-    def __init__(self, http_client: KaggleHttpClient):
-      self.blob_api_client = BlobApiClient(http_client)
-
-  class Education(object):
+  class Security(object):
     def __init__(self, http_client: KaggleHttpClient):
-      self.education_api_client = EducationApiClient(http_client)
+      self.oauth_client = OAuthClient(http_client)
 
   class Models(object):
     def __init__(self, http_client: KaggleHttpClient):
       self.model_api_client = ModelApiClient(http_client)
       self.model_client = ModelClient(http_client)
 
+  class Kernels(object):
+    def __init__(self, http_client: KaggleHttpClient):
+      self.kernels_api_client = KernelsApiClient(http_client)
+
   class Competitions(object):
     def __init__(self, http_client: KaggleHttpClient):
       self.competition_api_client = CompetitionApiClient(http_client)
 
+  class Education(object):
+    def __init__(self, http_client: KaggleHttpClient):
+      self.education_api_client = EducationApiClient(http_client)
+
   class Datasets(object):
     def __init__(self, http_client: KaggleHttpClient):
       self.dataset_api_client = DatasetApiClient(http_client)
 
-  class Admin(object):
+  class Users(object):
     def __init__(self, http_client: KaggleHttpClient):
-      self.inbox_file_client = InboxFileClient(http_client)
+      self.account_client = AccountClient(http_client)
 
-  class Security(object):
+  class Admin(object):
     def __init__(self, http_client: KaggleHttpClient):
-      self.oauth_client = OAuthClient(http_client)
+      self.inbox_file_client = InboxFileClient(http_client)
 
-  class Users(object):
+  class Blobs(object):
     def __init__(self, http_client: KaggleHttpClient):
-      self.account_client = AccountClient(http_client)
+      self.blob_api_client = BlobApiClient(http_client)
 
-  def __init__(self, env: KaggleEnv = None, verbose: bool = False, username: str = None, password: str = None):
-    self._http_client = http_client = KaggleHttpClient(env, verbose, self._renew_iap_token, username=username, password=password)
-    self.kernels = KaggleClient.Kernels(http_client)
-    self.blobs = KaggleClient.Blobs(http_client)
-    self.education = KaggleClient.Education(http_client)
+  def __init__(self, env: KaggleEnv = None, verbose: bool = False, username: str = None, password: str = None, api_token: str = None):
+    self._http_client = http_client = KaggleHttpClient(env, verbose, username=username, password=password, api_token=api_token)
+    self.security = KaggleClient.Security(http_client)
     self.models = KaggleClient.Models(http_client)
+    self.kernels = KaggleClient.Kernels(http_client)
     self.competitions = KaggleClient.Competitions(http_client)
+    self.education = KaggleClient.Education(http_client)
     self.datasets = KaggleClient.Datasets(http_client)
-    self.admin = KaggleClient.Admin(http_client)
-    self.security = KaggleClient.Security(http_client)
     self.users = KaggleClient.Users(http_client)
+    self.admin = KaggleClient.Admin(http_client)
+    self.blobs = KaggleClient.Blobs(http_client)
     self.username = username
     self.password = password
+    self.api_token = api_token
 
-  def http_client(self):
+  def http_client(self) -> str:
     return self._http_client
 
-  def _renew_iap_token(self):
+  def _renew_iap_token(self) -> str:
     return self.admin.admin_client.renew_iap_token()
 
   def __enter__(self):
diff --git a/src/kagglesdk/kaggle_env.py b/src/kagglesdk/kaggle_env.py
index ebcf4c2..732a416 100644
--- a/src/kagglesdk/kaggle_env.py
+++ b/src/kagglesdk/kaggle_env.py
@@ -1,12 +1,14 @@
 import logging
 import os
 from enum import Enum
+from pathlib import Path
 
 KAGGLE_NOTEBOOK_ENV_VAR_NAME = "KAGGLE_KERNEL_RUN_TYPE"
 KAGGLE_DATA_PROXY_URL_ENV_VAR_NAME = "KAGGLE_DATA_PROXY_URL"
 KAGGLE_API_V1_TOKEN_PATH = "KAGGLE_API_V1_TOKEN"
 
-logger = logging.getLogger(__name__)
+def get_logger():
+    return logging.getLogger(__name__)
 
 class KaggleEnv(Enum):
   LOCAL = 0  # localhost
@@ -50,10 +52,38 @@ def is_in_kaggle_notebook() -> bool:
   if os.getenv(KAGGLE_NOTEBOOK_ENV_VAR_NAME) is not None:
     if os.getenv(KAGGLE_DATA_PROXY_URL_ENV_VAR_NAME) is None:
       # Missing endpoint for the Jwt client
-      logger.warning(
+      get_logger().warning(
         "Can't use the Kaggle Cache. "
         f"The '{KAGGLE_DATA_PROXY_URL_ENV_VAR_NAME}' environment variable is not set."
       )
       return False
     return True
   return False
+
+def _get_access_token_from_file(path):
+  if not path:
+    return (None, None)
+  
+  token_path = Path(path)
+  if not token_path.exists():
+    return (None, None)
+  
+  token_value = token_path.read_text().strip()
+  if not token_value:
+    return (None, None)
+  
+  get_logger().debug(f"Using access token from file: \"{path}\"")
+  return (token_value, path)
+
+def get_access_token_from_env():
+  if is_in_kaggle_notebook():
+      token = _get_access_token_from_file(os.environ.get(KAGGLE_API_V1_TOKEN_PATH))
+      if token:
+        return (token, KAGGLE_API_V1_TOKEN_PATH)
+  
+  access_token = os.environ.get('KAGGLE_API_TOKEN')
+  if access_token is not None:
+    get_logger().debug("Using access token from KAGGLE_API_TOKEN environment variable")
+    return (access_token, 'KAGGLE_API_TOKEN')
+  
+  return (None, None)
diff --git a/src/kagglesdk/kaggle_http_client.py b/src/kagglesdk/kaggle_http_client.py
index 2b22820..6dd0e40 100644
--- a/src/kagglesdk/kaggle_http_client.py
+++ b/src/kagglesdk/kaggle_http_client.py
@@ -9,7 +9,7 @@
 import requests
 from urllib3.fields import RequestField
 
-from kagglesdk.kaggle_env import get_endpoint, get_env, is_in_kaggle_notebook, KAGGLE_API_V1_TOKEN_PATH, KaggleEnv
+from kagglesdk.kaggle_env import get_endpoint, get_env, is_in_kaggle_notebook, get_access_token_from_env, KaggleEnv
 from kagglesdk.kaggle_object import KaggleObject
 from typing import Type
 
@@ -94,9 +94,9 @@ def __init__(
       self,
       env: KaggleEnv = None,
       verbose: bool = False,
-      renew_iap_token=None,
-      username=None,
-      password=None,
+      username: str = None,
+      password: str = None,
+      api_token: str = None
   ):
     self._env = env or get_env()
     self._signed_in = None
@@ -105,6 +105,7 @@ def __init__(
     self._session = None
     self._username = username
     self._password = password
+    self._api_token = api_token
 
   def call(
       self,
@@ -295,7 +296,7 @@ def _try_fill_auth(self):
     if self._signed_in is not None:
       return
 
-    api_token = os.getenv('KAGGLE_API_TOKEN')
+    api_token = self._api_token or os.getenv('KAGGLE_API_TOKEN')
     if api_token is not None:
       self._session.auth = KaggleHttpClient.BearerAuth(api_token)
       self._signed_in = True
@@ -310,16 +311,11 @@ def _try_fill_auth(self):
       self._signed_in = True
       return
       
-    if is_in_kaggle_notebook():
-      token_file_path_str = os.environ.get(KAGGLE_API_V1_TOKEN_PATH)
-      if token_file_path_str:
-        token_path = Path(token_file_path_str)
-        if token_path.exists():
-          token_value = token_path.read_text().strip()
-          if token_value:
-            self._session.auth = KaggleHttpClient.BearerAuth(token_value)
-            self._signed_in = True
-            return
+    (api_token, _) = get_access_token_from_env()
+    if api_token is not None:
+      self._session.auth = KaggleHttpClient.BearerAuth(api_token)
+      self._signed_in = True
+      return
 
     self._signed_in = False
 
diff --git a/tests/unit_tests.py b/tests/unit_tests.py
index 9992d16..2dea37d 100644
--- a/tests/unit_tests.py
+++ b/tests/unit_tests.py
@@ -28,7 +28,6 @@
 # Give it the module: unit_tests.TestKaggleApi
 # Set the working directory to: kaggle-api/tests
 # Define some envars:
-# KAGGLE_API_ENDPOINT=http://localhost
 # KAGGLE_API_ENVIRONMENT=LOCALHOST
 # KAGGLE_CONFIG_DIR=/home/kaggle/.config/kaggle/dev
 # KAGGLE_KEY=local_api_token
diff --git a/tools/use-localhost.sh b/tools/use-localhost.sh
index a62190b..a5413ce 100755
--- a/tools/use-localhost.sh
+++ b/tools/use-localhost.sh
@@ -7,7 +7,7 @@ if [[ "$0" == "$BASH_SOURCE" ]]; then
   exit 1
 fi
 
-export KAGGLE_API_ENDPOINT=http://localhost
+export KAGGLE_API_ENVIRONMENT=LOCALHOST
 export KAGGLE_CONFIG_DIR=$(realpath "${XDG_CONFIG_HOME:-$HOME/.config}/kaggle/dev")
 
 KAGGLE_CONFIG_FILE="$KAGGLE_CONFIG_DIR/kaggle.json"
diff --git a/tools/use-prod.sh b/tools/use-prod.sh
index fb0fc86..03e132a 100755
--- a/tools/use-prod.sh
+++ b/tools/use-prod.sh
@@ -7,7 +7,7 @@ if [[ "$0" == "$BASH_SOURCE" ]]; then
   exit 1
 fi
 
-unset KAGGLE_API_ENDPOINT
+unset KAGGLE_API_ENVIRONMENT
 unset KAGGLE_CONFIG_DIR
 
 if ! [[ -f "${XDG_CONFIG_HOME:-$HOME/.config}/kaggle/kaggle.json" ]]; then