A functional customer comes and says 'I need a report' — where do you start?

The first step is to clarify the requirements and context:

• Report goal: What exactly does the client want to obtain? What business tasks or solutions should the report support?
• Content: What data should be included? What metrics, indicators, filters, or groupings are needed?
• Format and frequency: In what form is the report needed (table, charts, PDF, Excel)? How often should it be updated?
• Audience: Who will use the report? What are their requirements for detail and convenience?
• Data sources: Where to get the data? Is there access to the necessary systems?

After gathering this information, a technical assignment can be drafted, necessary resources identified, and report design started.

This approach helps avoid misunderstandings and makes the report as useful as possible.