To create a catalogue merge, you must first decide what kind of information you want in the finished publication. Knowing this information will help you decide the type of data source to create and use for the catalogue merge. A data source is a file that can be merged into a publication. Data sources are usually in a table format; therefore, if you are new to this use Excel to create the data source. When creating a data source the headings you choose will be the Data fields in the catalogue merge and are necessary. A sample data source is provided for this lesson, but if you want to create your own, feel free to open and view the one provided to get a feel of the layout required.