diff --git a/invokeai/app/services/events/__init__.py b/invokeai/app/services/events/__init__.py
index e69de29bb2..17407d3b72 100644
--- a/invokeai/app/services/events/__init__.py
+++ b/invokeai/app/services/events/__init__.py
@@ -0,0 +1 @@
+from .events_base import EventServiceBase  # noqa F401
diff --git a/invokeai/app/services/events/events_base.py b/invokeai/app/services/events/events_base.py
index dd4152e609..bfb982b4c0 100644
--- a/invokeai/app/services/events/events_base.py
+++ b/invokeai/app/services/events/events_base.py
@@ -1,5 +1,7 @@
 # Copyright (c) 2022 Kyle Schouviller (https://github.com/kyle0654)
 
+import traceback
+
 from typing import Any, Optional
 
 from invokeai.app.services.invocation_processor.invocation_processor_common import ProgressImage
@@ -313,3 +315,55 @@ class EventServiceBase:
             event_name="queue_cleared",
             payload={"queue_id": queue_id},
         )
+
+    def emit_model_install_started(self, source: str) -> None:
+        """
+        Emitted when an install job is started.
+
+        :param source: Source of the model; local path, repo_id or url
+        """
+        self.__emit_queue_event(
+            event_name="model_install_started",
+            payload={"source": source},
+        )
+
+    def emit_model_install_completed(self, source: str, dest: str) -> None:
+        """
+        Emitted when an install job is completed successfully.
+
+        :param source: Source of the model; local path, repo_id or url
+        :param dest: Destination of the model files; always a local path
+        """
+        self.__emit_queue_event(
+            event_name="model_install_completed",
+            payload={
+                "source": source,
+                "dest": dest,
+            },
+        )
+
+    def emit_model_install_error(self,
+                                 source:str,
+                                 exception: Exception,
+                                 ) -> None:
+        """
+        Emitted when an install job encounters an exception.
+
+        :param source: Source of the model
+        :param exception: The exception that raised the error
+        """
+
+        # Revisit:
+        # it makes more sense to receive an exception and break it out
+        # into error_type and error here, rather than at the caller's side
+        error_type = exception.__class__.__name__,
+        error = traceback.format_exc(),
+
+        self.__emit_queue_event(
+            event_name="model_install_error",
+            payload={
+                "source": source,
+                "error_type": error_type,
+                "error": error,
+            },
+        )
diff --git a/invokeai/app/services/model_install/__init__.py b/invokeai/app/services/model_install/__init__.py
new file mode 100644
index 0000000000..772cd9a9f0
--- /dev/null
+++ b/invokeai/app/services/model_install/__init__.py
@@ -0,0 +1 @@
+from .model_install_default import ModelInstallService  # noqa F401
diff --git a/invokeai/app/services/model_install/model_install_base.py b/invokeai/app/services/model_install/model_install_base.py
new file mode 100644
index 0000000000..fcf3ab9d17
--- /dev/null
+++ b/invokeai/app/services/model_install/model_install_base.py
@@ -0,0 +1,228 @@
+from abc import ABC, abstractmethod
+from enum import Enum
+from pathlib import Path
+from typing import Dict, Optional, Union
+from pydantic import BaseModel, Field
+from pydantic.networks import AnyHttpUrl
+
+from invokeai.app.services.model_records import  ModelRecordServiceBase
+from invokeai.app.services.config import InvokeAIAppConfig
+from invokeai.app.services.events import EventServiceBase
+
+
+class InstallStatus(str, Enum):
+    """State of an install job running in the background."""
+
+    WAITING = "waiting"      # waiting to be dequeued
+    COMPLETED = "completed"  # finished running
+    ERROR = "error"          # terminated with an error message
+
+
+class ModelInstallStatus(BaseModel):
+    status: InstallStatus = Field(default=InstallStatus.WAITING, description="Current status of install process")  # noqa #501
+    error: Optional[Exception] = Field(default=None, description="Exception that led to status==ERROR")  # noqa #501
+
+
+class ModelInstallServiceBase(ABC):
+    """Abstract base class for InvokeAI model installation."""
+
+    @abstractmethod
+    def __init__(
+            self,
+            config: InvokeAIAppConfig,
+            store: ModelRecordServiceBase,
+            event_bus: Optional["EventServiceBase"] = None,
+    ):
+        """
+        Create ModelInstallService object.
+
+        :param config: Systemwide InvokeAIAppConfig.
+        :param store: Systemwide ModelConfigStore
+        :param event_bus: InvokeAI event bus for reporting events to.
+        """
+        pass
+
+    @property
+    @abstractmethod
+    def config(self) -> InvokeAIAppConfig:
+        """Return the app_config used by the installer."""
+        pass
+
+    @property
+    @abstractmethod
+    def store(self) -> ModelRecordServiceBase:
+        """Return the storage backend used by the installer."""
+        pass
+
+    @abstractmethod
+    def register_path(
+            self,
+            model_path: Union[Path, str],
+            name: Optional[str] = None,
+            description: Optional[str] = None,
+            metadata: Optional[Dict[str, str]] = None,
+    ) -> str:
+        """
+        Probe and register the model at model_path.
+
+        This keeps the model in its current location.
+
+        :param model_path: Filesystem Path to the model.
+        :param name: Name for the model (optional)
+        :param description: Description for the model (optional)
+        :param metadata: Dict of attributes that will override probed values.
+        :returns id: The string ID of the registered model.
+        """
+        pass
+
+    @abstractmethod
+    def install_path(
+            self,
+            model_path: Union[Path, str],
+            name: Optional[str] = None,
+            description: Optional[str] = None,
+            metadata: Optional[Dict[str, str]] = None,
+    )-> str:
+        """
+        Probe, register and install the model in the models directory.
+
+        This moves the model from its current location into
+        the models directory handled by InvokeAI.
+
+        :param model_path: Filesystem Path to the model.
+        :param name: Name for the model (optional)
+        :param description: Description for the model (optional)
+        :param metadata: Dict of attributes that will override probed values.
+        :returns id: The string ID of the registered model.
+        """
+        pass
+
+    @abstractmethod
+    def install_model(
+            self,
+            source: Union[str, Path, AnyHttpUrl],
+            inplace: bool = True,
+            name: Optional[str] = None,
+            description: Optional[str] = None,
+            variant: Optional[str] = None,
+            subfolder: Optional[str] = None,
+            metadata: Optional[Dict[str, str]] = None,
+            access_token: Optional[str] = None,
+    ) -> ModelInstallStatus:
+        """Install the indicated model.
+
+        :param source: Either a URL or a HuggingFace repo_id.
+
+        :param inplace: If True, local paths will not be moved into
+         the models directory, but registered in place (the default).
+
+        :param variant: For HuggingFace models, this optional parameter
+         specifies which variant to download (e.g. 'fp16')
+
+        :param subfolder: When downloading HF repo_ids this can be used to
+         specify a subfolder of the HF repository to download from.
+
+        :param metadata: Optional dict. Any fields in this dict
+         will override corresponding probe fields. Use it to override
+         `base_type`, `model_type`, `format`, `prediction_type`, `image_size`,
+         and `ztsnr_training`.
+
+        :param access_token: Access token for use in downloading remote
+         models.
+
+        This will download the model located at `source`,
+        probe it, and install it into the models directory.
+        This call is executed asynchronously in a separate
+        thread and will issue the following events on the event bus:
+
+             - model_install_started
+             - model_install_error
+             - model_install_completed
+
+        The `inplace` flag does not affect the behavior of downloaded
+        models, which are always moved into the `models` directory.
+
+        The call returns a ModelInstallStatus object which can be
+        polled to learn the current status and/or error message.
+
+        Variants recognized by HuggingFace currently are:
+        1. onnx
+        2. openvino
+        3. fp16
+        4. None (usually returns fp32 model)
+
+        """
+        pass
+
+    @abstractmethod
+    def wait_for_installs(self) -> Dict[Union[str, Path, AnyHttpUrl], Optional[str]]:
+        """
+        Wait for all pending installs to complete.
+
+        This will block until all pending downloads have
+        completed, been cancelled, or errored out. It will
+        block indefinitely if one or more jobs are in the
+        paused state.
+
+        It will return a dict that maps the source model
+        path, URL or repo_id to the ID of the installed model.
+        """
+        pass
+
+    @abstractmethod
+    def scan_directory(self, scan_dir: Path, install: bool = False) -> List[str]:
+        """
+        Recursively scan directory for new models and register or install them.
+
+        :param scan_dir: Path to the directory to scan.
+        :param install: Install if True, otherwise register in place.
+        :returns list of IDs: Returns list of IDs of models registered/installed
+        """
+        pass
+
+    @abstractmethod
+    def sync_to_config(self):
+        """Synchronize models on disk to those in memory."""
+        pass
+
+    @abstractmethod
+    def hash(self, model_path: Union[Path, str]) -> str:
+        """
+        Compute and return the fast hash of the model.
+
+        :param model_path: Path to the model on disk.
+        :return str: FastHash of the model for use as an ID.
+        """
+        pass
+
+    # The following are internal methods
+    @abstractmethod
+    def _create_name(self, model_path: Union[Path, str]) -> str:
+        """
+        Creates a default name for the model.
+
+        :param model_path: Path to the model on disk.
+        :return str: Model name
+        """
+        pass
+
+    @abstractmethod
+    def _create_description(self, model_path: Union[Path, str]) -> str:
+        """
+        Creates a default description for the model.
+
+        :param model_path: Path to the model on disk.
+        :return str: Model description
+        """
+        pass
+
+    @abstractmethod
+    def _create_id(self, model_path: Union[Path, str], name: Optional[str] = None) -> str:
+        """
+        Creates a unique ID for the model for use with the model records module.  # noqa E501
+
+        :param model_path: Path to the model on disk.
+        :param name: (optional) non-default name for the model
+        :return str: Unique ID
+        """
+        pass
diff --git a/invokeai/app/services/model_install/model_install_default.py b/invokeai/app/services/model_install/model_install_default.py
new file mode 100644
index 0000000000..8ed61b8b36
--- /dev/null
+++ b/invokeai/app/services/model_install/model_install_default.py
@@ -0,0 +1,78 @@
+from pathlib import Path
+from typing import Dict, Optional, Union
+from pydantic import BaseModel, Field
+from queue import Queue
+from pydantic.networks import AnyHttpUrl
+
+from .model_install_base import InstallStatus, ModelInstallStatus, ModelInstallServiceBase
+from invokeai.app.services.config import InvokeAIAppConfig
+from invokeai.app.services.model_records import ModelRecordServiceBase
+from invokeai.app.services.events import EventServiceBase
+
+class ModelInstallService(ModelInstallBase, BaseModel):
+    """class for InvokeAI model installation."""
+
+    config: InvokeAIAppConfig
+    store: ModelRecordServiceBase
+    event_bus: Optional[EventServiceBase] = Field(default=None)
+    install_queue: Queue = Field(default_factory=Queue)
+
+    def register_path(
+            self,
+            model_path: Union[Path, str],
+            name: Optional[str] = None,
+            description: Optional[str] = None,
+            metadata: Optional[Dict[str, str]] = None,
+    ) -> str:
+        raise NotImplementedError
+
+    def install_path(
+            self,
+            model_path: Union[Path, str],
+            name: Optional[str] = None,
+            description: Optional[str] = None,
+            metadata: Optional[Dict[str, str]] = None,
+    ) -> str:
+        raise NotImplementedError
+
+    def install_model(
+            self,
+            source: Union[str, Path, AnyHttpUrl],
+            inplace: bool = True,
+            name: Optional[str] = None,
+            description: Optional[str] = None,
+            variant: Optional[str] = None,
+            subfolder: Optional[str] = None,
+            metadata: Optional[Dict[str, str]] = None,
+            access_token: Optional[str] = None,
+    ) -> ModelInstallStatus:
+        raise NotImplementedError
+
+    def wait_for_installs(self) -> Dict[Union[str, Path, AnyHttpUrl], Optional[str]]:
+        raise NotImplementedError
+
+    def scan_directory(self, scan_dir: Path, install: bool = False) -> List[str]:
+        raise NotImplementedError
+
+    def sync_to_config(self):
+        raise NotImplementedError
+
+    def hash(self, model_path: Union[Path, str]) -> str:
+        raise NotImplementedError
+
+    # The following are internal methods
+    def _create_name(self, model_path: Union[Path, str]) -> str:
+        model_path = Path(model_path)
+        if model_path.suffix in {'.safetensors', '.bin', '.pt', '.ckpt'}:
+            return model_path.stem
+        else:
+            return model_path.name
+
+    def _create_description(self, model_path: Union[Path, str]) -> str:
+        info: ModelProbeInfo = ModelProbe.probe(Path(model_path))
+        name: str = name or self._create_name(model_path)
+        return f"a {info.model_type} model based on {info.base_type}"
+
+    def _create_id(self, model_path: Union[Path, str], name: Optional[str] = None) -> str:
+        name: str = name or self._create_name(model_path)
+        raise NotImplementedError