After looking through this forum I am struck by the number of people with PortalId/UserId Parameter problems, from developers who invariably have asked you to provide some document that covers this subject. I cannot understand why you don't. I  have written several times to you and several times you have very kindly replied without really understanding my question and, consequently, I have got nowhere with your support.

The issue must be a common enough problem and for the benefit of your readers I will outline it:-   I have a report that can be generated from several database events and each of these events has a portal identity. I need to produce a Cascaded Parameter, 'PortalId', to pass back to the DataSet that Report Server uses to populate the Events dropdown, in order to limit the option of reports to those that pertain to that portal. Having selected the Event the user may then hit the View Report. Quite simple really, but I have been trying for several days to pass back PortalId.Value, including (portalid.value, PortalID.value, PORTALID.value plus many other combinations), which the RS2005 Report Viewer is supposed to substitute, at least, so I am led to believe. But I can't make it work.  I have tried making the Report Parameter hidden and internal but again to no avail. I have created the parameter through a Select Dataset to make sure that the Cascaded parameters actually work and they do. So, when I then set PortalId then to hidden (or internal) then nothing gets substituted by DNN RS2005.

I cannot believe that the developers have never tried this most common of all Report requirements. If so, why do they keep it such a well-guarded secret as to how it is achieved? Why not provide an exhaustive document of examples that show how this works. In view of the number of queries regarding this subject, if I am thick, then I am in good company.

Nick Chance, Developer, and currently heading for a mental breakdown. 

[Incidentally, on the subject of issues, the Preview button below only showed half my message when I clicked it. When I attempted to go back and post the message, the whole thing went tits up and I've had to re-enter the whole message again. Perhaps it needs testing?]

Many, many thanks BEN for all of your help and support. Your example has helped enormously, as well as the  advice you gave about utilising a sproc rather than in-line text sql, which seems to have been the key to unlocking this.

To anyone else who gets the awful