Data catalogue

A data catalogue is like a library catalogue, but for the company's data. For each data set (a table, a file, a report) it states what it contains, what each field means, which system it lives in, who its Data Owner is, how it is classified, how often it is updated and where it comes from.

Without a catalogue, people keep asking "where is the data for X?" and end up using different versions. With one, data can be found, understood and reused, and duplicated work is avoided.

You can start with a simple spreadsheet of your 20 or 30 most important data sets and move to a dedicated tool later. What matters is not the tool but that Data Stewards keep it up to date.