A model, which is a collection of elements that represent a distributable software solution, can be created using a wizard.

To create a model, navigate to Dynamics 365 > Model Management > Create model.

It’ll open a wizard for creating a model. In this window, we can specify the model name. For this example, the model is called “AirlineReservation.”

For the “publisher,” we type in our name or the publisher’s name.

Give a short description in the model description.

Give the “model display name.” This is the name that’ll be seen in the Application Explorer in the Application Object Tree (AOT).

Click “Next.”

Here, a page will open with two options.

If “Select existing package” is chosen, that means we’ll be using our over-layering or customization development approach. In this, we must select a model that contains the elements we wish to customize as a referenced model in the wizard. In this way, our new model has access to those elements.

If “Create new package” is chosen, this implies we’re going to use the extension model approach. Developing this way allows us to access the elements from any models we selected as referenced models. We can create new elements and add functionality to the existing code.

In the “AirlineReservation” model, we’re going to create a new package (we’re using the extension development approach). Select the “Create new package” option and click “Next.”

Now we’re going to select our referenced models. This means we’re choosing the other models our “AirlineReservation” model can see, or which elements it’ll have access to.

Here, we’ll only select “ApplicationPlatform” and then choose “Next.”

This will open a summary window of our model name, display name, publisher and the referenced packages.

Select the options “Create new project” and “Make this my default model for new projects.”

Click “Finish.”

This will open a screen to create a project. Here, give the project name—in this case, “AirlineProject”—and click “OK.”

This finalizes the model and project creation. It’ll open the project in the solution explorer, displaying the project and model names.

We can now add new elements to this project.