It is possible. If your web service just takes/returns primitive parameters it is easy. If you get into passing objects around, you'll find it more difficult, requiring rather complex serialization. This basic idea is available using AJAX. Though it's not limited to calling a webservice, you could just call a web page with a query string. There are a number of AJAX toolkits out there that should make this reasonably painless for you. See Microsoft ATLAS ATLAS CTP Or just look for AJAX frameworks. There are several. Any of them will provide you with numerous examples of the serialization and usage of XmlHttpRequest in javascript. -- modified at 15:39 Tuesday 1st August, 2006