I often have many 1:n relationships to print on one report. For example a report should include a customer with 1:n contacts, with 1:n projects, with 1:n keywords, and so on. For this, I would create small reports for contacts, projects, keywords and include all 3 into a main report for the customer, linking them over primary key / foreign key as subreport-parameters. This is like the concept in Microsoft Access reports which I find is very powerful. In Filemaker I only can do one 1:n relationship by using a listview and placing the 1-part for example in the preceding summary section and the n-part in the detail section, but I can't have lot's of "detail-sections". With subreports I could.