Thanks to all who responded with help, although I wasn't successful with any of the scripts/tools sent to me (which could very well be a user problem)! I had to do it the old-fashioned way of cutting polygons. I will have to figure it out as I will be doing more of this work - I may just need to play around with it a bit more. Hope others have more luck than I. Although too large to include, Ivan also included the following - thanks. "'DEM and Hydrological Analysis' published by ARCVIEW-L on March 16, 2001. Reading it before performing hydrological analysis which involves DEMs may help you to avoid and sort out some frequently encountered problems." - Ivan kt ************* Hi Karina, I've attached an avenue script that I downloaded from ESRI. As long as you have a good DEM it seems to work. Lea <> ********************* Karina, There is an extension which should be on the scripts page at ESRI.COM which I think is called BASIN1 which will do exactly what you want. Its actually pretty useful and we use it a lot for working out catchment areas at certain points along streams etc. It requires Spatial Analyst but I assume you need this to do anything with DEMs. Cheers Tim ********************** Yes it is - you can try and do this with my script: http://gis.esri.com/arcscripts/details.cfm?CFGRIDKEY=951497255 Be aware though that this script will only return the partial watersheds from one point up to the next point. If you want to get the entire watershed for each point (i.e., overlaying watersheds) you need to give the results some manual follow-up treatment. If you need any help with this, let me know. Best regards, Fridjof Schmidt ********************************************************************** Mrs Karina Tedesco CPAg MAIAST Brown & Root Services Asia Pacific Pty Ltd 47 Burswood Rd Victoria Park WA 6100 Ph: 08 9362 5900 Fx: 08 9362 5627