Do not add subreports which are called each time a master record is fetched for any report working with a large set of data. Instead, add the subreport query to the main report, put change the query setting to joins ( inner , outer ) between the main report query and subreport query. You can also add another group in place of the subreport that uses the subreport query. This results in the same report output and reduces the round-trip database calls made by BusinessObjects for the report without compromising on performance.