diff --git a/tests/concurrency.py b/tests/concurrency.py
index a8ed558..d5ce803 100644
--- a/tests/concurrency.py
+++ b/tests/concurrency.py
@@ -5,11 +5,11 @@ Async environment-agnostic concurrency utilities that are only used in tests.
 import asyncio
 
 import sniffio
-import trio
 
 
 async def sleep(seconds: float) -> None:
     if sniffio.current_async_library() == "trio":
+        import trio
         await trio.sleep(seconds)  # pragma: no cover
     else:
         await asyncio.sleep(seconds)