diff --git a/examples/prompttests/test_openai_chat.py b/examples/prompttests/test_openai_chat.py
index c21a73b..47f71aa 100644
--- a/examples/prompttests/test_openai_chat.py
+++ b/examples/prompttests/test_openai_chat.py
@@ -14,9 +14,6 @@
 from prompttools.mock.mock import mock_openai_completion_fn
 
 
-client = OpenAI()
-
-
 if not (("OPENAI_API_KEY" in os.environ) or ("DEBUG" in os.environ)):
     print("Error: This example requires you to set either your OPENAI_API_KEY or DEBUG=1")
     exit(1)
@@ -48,6 +45,7 @@ def json_completion_fn(prompt: str):
     if os.getenv("DEBUG", default=False):
         response = mock_openai_completion_fn(**{"prompt": prompt})
     else:
+        client = OpenAI()
         response = client.completions.create(model="babbage-002", prompt=prompt)
     return response.choices[0].text
 
@@ -65,6 +63,7 @@ def completion_fn(prompt: str):
     if os.getenv("DEBUG", default=False):
         response = mock_openai_completion_fn(**{"prompt": prompt})
     else:
+        client = OpenAI()
         response = client.completions.create(prompt)
     return response.choices[0].text
 
diff --git a/prompttools/utils/autoeval.py b/prompttools/utils/autoeval.py
index 9cd3d95..2dc4167 100644
--- a/prompttools/utils/autoeval.py
+++ b/prompttools/utils/autoeval.py
@@ -23,7 +23,6 @@
 RESPONSE: {{response}}
 ANSWER:
 """
-client = OpenAI()
 
 
 def _get_messages(prompt: str, response: str):
@@ -49,6 +48,7 @@ def compute(prompt: str, response: str, model: str = "gpt-4") -> float:
     """
     if not os.environ["OPENAI_API_KEY"]:
         raise PromptToolsUtilityError
+    client = OpenAI()
     evaluation = client.chat.completions.create(model=model, messages=_get_messages(prompt, response))
     return 1.0 if "RIGHT" in evaluation.choices[0].message.content else 0.0
 
diff --git a/prompttools/utils/autoeval_from_expected.py b/prompttools/utils/autoeval_from_expected.py
index cb16b39..8dcdf61 100644
--- a/prompttools/utils/autoeval_from_expected.py
+++ b/prompttools/utils/autoeval_from_expected.py
@@ -27,8 +27,6 @@
 ANSWER:
 """
 
-client = OpenAI()
-
 
 def _get_messages(prompt: str, expected: str, response: str):
     environment = jinja2.Environment()
@@ -53,6 +51,9 @@ def compute(prompt: str, expected: str, response: str, model: str = "gpt-4") ->
     """
     if not os.environ["OPENAI_API_KEY"]:
         raise PromptToolsUtilityError("Missing API key for evaluation.")
+    global client
+    if client is None:
+        client = OpenAI()
     evaluation = client.chat.completions.create(model=model, messages=_get_messages(prompt, expected, response))
     return 1.0 if "RIGHT" in evaluation.choices[0].message.content else 0.0
 
diff --git a/prompttools/utils/autoeval_with_docs.py b/prompttools/utils/autoeval_with_docs.py
index 0cbd696..f7962a9 100644
--- a/prompttools/utils/autoeval_with_docs.py
+++ b/prompttools/utils/autoeval_with_docs.py
@@ -27,9 +27,6 @@
 """
 
 
-client = OpenAI()
-
-
 def _get_messages(documents: list[str], response: str):
     environment = jinja2.Environment()
     template = environment.from_string(EVALUATION_USER_TEMPLATE)
@@ -52,6 +49,7 @@ def compute(documents: list[str], response: str, model: str = "gpt-4") -> float:
     """
     if not os.environ["OPENAI_API_KEY"]:
         raise PromptToolsUtilityError
+    client = OpenAI()
     evaluation = client.chat.completions.create(model=model, messages=_get_messages(documents, response))
     score_text = evaluation.choices[0].message.content
     return int(score_text)
diff --git a/prompttools/utils/expected.py b/prompttools/utils/expected.py
index aa2e07c..6d8244d 100644
--- a/prompttools/utils/expected.py
+++ b/prompttools/utils/expected.py
@@ -12,9 +12,6 @@
 from . import similarity
 
 
-client = OpenAI()
-
-
 def compute(prompt: str, model: str = "gpt-4") -> str:
     r"""
     Computes the expected result of a given prompt by using a high
@@ -27,6 +24,7 @@ def compute(prompt: str, model: str = "gpt-4") -> str:
     """
     if not os.environ["OPENAI_API_KEY"]:
         raise PromptToolsUtilityError
+    client = OpenAI()
     response = client.chat.completions.create(model=model, prompt=prompt)
     return response.choices[0].message.content