# Cadcorp SIS

The Cadcorp Spatial Information System® (Cadcorp SIS®) is an integrated family of geospatial products comprising desktop, web, and developer applications.

Cadcorp SIS Desktop connects directly to the Ordnance Survey Data Hub through dedicated wizards.

## What you need

* OS Maps API added to an API project in the OS Data Hub with an API Key; see [Getting started with an API project](/os-apis/core-concepts/getting-started-with-an-api-project.md) for more information
* Cadcorp SIS version SIS 9 or later

{% hint style="info" %}
**Note**: We used Cadcorp version 9.1.1668 to create these instructions.
{% endhint %}

## Instructions

{% stepper %}
{% step %}
**Add overlay**

Once a new map has been set up, in the Home tab, click *Add Overlay*.

<figure><img src="/files/liC826E9WWIAtJl8YG5E" alt="Cadcorp SIS Desktop UI showing Home > Add Overlay navigation option"><figcaption><p>Cadcorp SIS Desktop UI showing Home > Add Overlay navigation option</p></figcaption></figure>
{% endstep %}

{% step %}
**Select API**

In the Overlay Types dialog:

* Select *Ordnance Survey (GB) > OS (GB) Data Hub*, and then click *Next*.

In the OS (GB) Data Hub dialog:

* Select \_OS Maps API.
* **API Key**: Enter your API key (If you **do not have** an API key this can be left blank but will r*estrict your access to free open data*).
* **Premium/Public Sector Plan**: Select this option if you have this plan.
* **Save in the UI settings database (encrypted)**: Select this option.
* Click *Next*.

<figure><img src="/files/43MTlIl38LNBsQKlGXmr" alt="Cadcorp SIS Desktop  OS (GB) Data Hub dialog"><figcaption></figcaption></figure>
{% endstep %}

{% step %}
**Adding layers to the map**

In the OS (GB) Data Hub Maps API Layers dialog, select your preferred layer, and then click *Finish* to save the information and close the dialog.

<figure><img src="/files/TUGW2zr5QgOjeqlyS306" alt="Cadcorp SIS Desktop OS (GB) Data Hub Maps API Layers dialog"><figcaption></figcaption></figure>

*The selected layer will then display in the* SIS Workspace Definition (SWD) \_and the data will display in the map area:

<figure><img src="/files/xMvwiPe5CHEAYLGLOPR0" alt="Cadcorp SIS Desktop UI showing OS Maps API data in the map area"><figcaption></figcaption></figure>
{% endstep %}
{% endstepper %}


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