diff --git a/README.md b/README.md
index ee6e540..c29202c 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,9 @@ This package provides:
 
 Documentation is available at [https://abetlen.github.io/llama-cpp-python](https://abetlen.github.io/llama-cpp-python).
 
+Detailed MacOS Metal GPU install documentation is available at [docs/macos_install.md](docs/macos_install.md)
+
+
 ## Installation from PyPI (recommended)
 
 Install from PyPI (requires a c compiler):
@@ -25,7 +28,7 @@ Install from PyPI (requires a c compiler):
 pip install llama-cpp-python
 ```
 
-The above command will attempt to install the package and build build `llama.cpp` from source.
+The above command will attempt to install the package and build `llama.cpp` from source.
 This is the recommended installation method as it ensures that `llama.cpp` is built with the available optimizations for your system.
 
 If you have previously installed `llama-cpp-python` through pip and want to upgrade your version or rebuild the package with different  compiler options, please add the following flags to ensure that the package is rebuilt correctly:
diff --git a/docs/macos_install.md b/docs/macos_install.md
new file mode 100644
index 0000000..7d46bc4
--- /dev/null
+++ b/docs/macos_install.md
@@ -0,0 +1,62 @@
+
+# llama-cpp-python - MacOS Install with Metal GPU
+
+
+**(1) Make sure you have xcode installed... at least the command line parts**
+```
+# check the path of your xcode install 
+xcode-select -p
+
+# xcode installed returns
+# /Applications/Xcode-beta.app/Contents/Developer
+
+# if xcode is missing then install it... it takes ages;
+xcode-select --install
+```
+
+**(2) Install the conda version for MacOS that supports Metal GPU**
+```
+wget https://github.com/conda-forge/miniforge/releases/latest/download/Miniforge3-MacOSX-arm64.sh
+bash Miniforge3-MacOSX-arm64.sh
+```
+
+**(3) Make a conda environment**
+```
+conda create -n llama python=3.9.16
+conda activate llama
+```
+
+**(4) Install the LATEST llama-cpp-python.. which, as of just today, happily supports MacOS Metal GPU**  
+    *(you needed xcode installed in order pip to build/compile the C++ code)*
+```
+pip uninstall llama-cpp-python -y
+CMAKE_ARGS="-DLLAMA_METAL=on" FORCE_CMAKE=1 pip install -U llama-cpp-python --no-cache-dir
+pip install 'llama-cpp-python[server]'
+
+# you should now have llama-cpp-python v0.1.62 installed
+llama-cpp-python         0.1.62      
+
+```
+
+**(4) Download a v3 ggml llama/vicuna/alpaca model**
+ - **ggmlv3**
+ - file name ends with **q4_0.bin** - indicating it is 4bit quantized, with quantisation method 0
+
+https://huggingface.co/vicuna/ggml-vicuna-13b-1.1/blob/main/ggml-vic13b-q4_0.bin
+https://huggingface.co/vicuna/ggml-vicuna-13b-1.1/blob/main/ggml-vic13b-uncensored-q4_0.bin
+https://huggingface.co/TheBloke/LLaMa-7B-GGML/blob/main/llama-7b.ggmlv3.q4_0.bin
+https://huggingface.co/TheBloke/LLaMa-13B-GGML/blob/main/llama-13b.ggmlv3.q4_0.bin
+
+
+**(6) run the llama-cpp-python API server with MacOS Metal GPU support**
+```
+# config your ggml model path
+# make sure it is ggml v3
+# make sure it is q4_0
+export MODEL=[path to your llama.cpp ggml models]]/[ggml-model-name]]q4_0.bin
+python3 -m llama_cpp.server --model $MODEL  --n_gpu_layers 1
+```
+
+***Note:** If you omit the `--n_gpu_layers 1` then CPU will be used*
+
+
diff --git a/llama_cpp/llama.py b/llama_cpp/llama.py
index 4b6ce8c..46a9aeb 100644
--- a/llama_cpp/llama.py
+++ b/llama_cpp/llama.py
@@ -1378,6 +1378,7 @@ class Llama:
         mirostat_tau: float = 5.0,
         mirostat_eta: float = 0.1,
         model: Optional[str] = None,
+        logits_processor: Optional[LogitsProcessorList] = None,
     ) -> Union[ChatCompletion, Iterator[ChatCompletionChunk]]:
         """Generate a chat completion from a list of messages.
 
@@ -1419,6 +1420,7 @@ class Llama:
             mirostat_tau=mirostat_tau,
             mirostat_eta=mirostat_eta,
             model=model,
+            logits_processor=logits_processor,
         )
         if stream:
             chunks: Iterator[CompletionChunk] = completion_or_chunks  # type: ignore
diff --git a/llama_cpp/server/app.py b/llama_cpp/server/app.py
index e248472..999d1e6 100644
--- a/llama_cpp/server/app.py
+++ b/llama_cpp/server/app.py
@@ -259,13 +259,14 @@ class CreateCompletionRequest(BaseModel):
     )
     presence_penalty: Optional[float] = presence_penalty_field
     frequency_penalty: Optional[float] = frequency_penalty_field
+    logit_bias: Optional[Dict[str, float]] = Field(None)
+    logit_bias_type: Optional[Literal["input_ids", "tokens"]] = Field(None)
 
     # ignored or currently unsupported
     model: Optional[str] = model_field
     n: Optional[int] = 1
     logprobs: Optional[int] = Field(None)
     best_of: Optional[int] = 1
-    logit_bias: Optional[Dict[str, float]] = Field(None)
     user: Optional[str] = Field(None)
 
     # llama.cpp specific parameters
@@ -284,6 +285,39 @@ class CreateCompletionRequest(BaseModel):
 CreateCompletionResponse = create_model_from_typeddict(llama_cpp.Completion)
 
 
+def make_logit_bias_processor(
+    llama: llama_cpp.Llama,
+    logit_bias: Dict[str, float],
+    logit_bias_type: Optional[Literal["input_ids", "tokens"]],
+):
+    if logit_bias_type is None:
+        logit_bias_type = "input_ids"
+
+    to_bias: Dict[int, float] = {}
+    if logit_bias_type == "input_ids":
+        for input_id, score in logit_bias.items():
+            input_id = int(input_id)
+            to_bias[input_id] = score
+
+    elif logit_bias_type == "tokens":
+        for token, score in logit_bias.items():
+            token = token.encode('utf-8')
+            for input_id in llama.tokenize(token, add_bos=False):
+                to_bias[input_id] = score
+
+    def logit_bias_processor(
+        input_ids: List[int],
+        scores: List[float],
+    ) -> List[float]:
+        new_scores = [None] * len(scores)
+        for input_id, score in enumerate(scores):
+            new_scores[input_id] = score + to_bias.get(input_id, 0.0)
+
+        return new_scores
+
+    return logit_bias_processor
+
+
 @router.post(
     "/v1/completions",
     response_model=CreateCompletionResponse,
@@ -301,9 +335,16 @@ async def create_completion(
         "n",
         "best_of",
         "logit_bias",
+        "logit_bias_type",
         "user",
     }
     kwargs = body.dict(exclude=exclude)
+
+    if body.logit_bias is not None:
+        kwargs['logits_processor'] = llama_cpp.LogitsProcessorList([
+            make_logit_bias_processor(llama, body.logit_bias, body.logit_bias_type),
+        ])
+
     if body.stream:
         send_chan, recv_chan = anyio.create_memory_object_stream(10)
 
@@ -382,11 +423,12 @@ class CreateChatCompletionRequest(BaseModel):
     stream: bool = stream_field
     presence_penalty: Optional[float] = presence_penalty_field
     frequency_penalty: Optional[float] = frequency_penalty_field
+    logit_bias: Optional[Dict[str, float]] = Field(None)
+    logit_bias_type: Optional[Literal["input_ids", "tokens"]] = Field(None)
 
     # ignored or currently unsupported
     model: Optional[str] = model_field
     n: Optional[int] = 1
-    logit_bias: Optional[Dict[str, float]] = Field(None)
     user: Optional[str] = Field(None)
 
     # llama.cpp specific parameters
@@ -423,9 +465,16 @@ async def create_chat_completion(
     exclude = {
         "n",
         "logit_bias",
+        "logit_bias_type",
         "user",
     }
     kwargs = body.dict(exclude=exclude)
+
+    if body.logit_bias is not None:
+        kwargs['logits_processor'] = llama_cpp.LogitsProcessorList([
+            make_logit_bias_processor(llama, body.logit_bias, body.logit_bias_type),
+        ])
+
     if body.stream:
         send_chan, recv_chan = anyio.create_memory_object_stream(10)