diff --git a/README.md b/README.md
index 81fdc4a24..65654f5a0 100644
--- a/README.md
+++ b/README.md
@@ -26,9 +26,9 @@
 SAM 2 needs to be installed first before use. The code requires `python>=3.10`, as well as `torch>=2.3.1` and `torchvision>=0.18.1`. Please follow the instructions [here](https://pytorch.org/get-started/locally/) to install both PyTorch and TorchVision dependencies. You can install SAM 2 on a GPU machine using:
 
 ```bash
-git clone https://github.com/facebookresearch/sam2.git
+git clone https://github.com/facebookresearch/sam2.git && cd sam2
 
-cd sam2 & pip install -e .
+pip install -e .
 ```
 If you are installing on Windows, it's strongly recommended to use [Windows Subsystem for Linux (WSL)](https://learn.microsoft.com/en-us/windows/wsl/install) with Ubuntu.
 
diff --git a/sam2/build_sam.py b/sam2/build_sam.py
index 7346adc0e..7cfc45139 100644
--- a/sam2/build_sam.py
+++ b/sam2/build_sam.py
@@ -5,12 +5,33 @@
 # LICENSE file in the root directory of this source tree.
 
 import logging
+import os
 
 import torch
 from hydra import compose
 from hydra.utils import instantiate
 from omegaconf import OmegaConf
 
+import sam2
+
+# Check if the user is running Python from the parent directory of the sam2 repo
+# (i.e. the directory where this repo is cloned into) -- this is not supported since
+# it could shadow the sam2 package and cause issues.
+if os.path.isdir(os.path.join(sam2.__path__[0], "sam2")):
+    # If the user has "sam2/sam2" in their path, they are likey importing the repo itself
+    # as "sam2" rather than importing the "sam2" python package (i.e. "sam2/sam2" directory).
+    # This typically happens because the user is running Python from the parent directory
+    # that contains the sam2 repo they cloned.
+    raise RuntimeError(
+        "You're likely running Python from the parent directory of the sam2 repository "
+        "(i.e. the directory where https://github.com/facebookresearch/sam2 is cloned into). "
+        "This is not supported since the `sam2` Python package could be shadowed by the "
+        "repository name (the repository is also named `sam2` and contains the Python package "
+        "in `sam2/sam2`). Please run Python from another directory (e.g. from the repo dir "
+        "rather than its parent dir, or from your home directory) after installing SAM 2."
+    )
+
+
 HF_MODEL_ID_TO_FILENAMES = {
     "facebook/sam2-hiera-tiny": (
         "configs/sam2/sam2_hiera_t.yaml",