hello all, this is my first post in this forum... this question encompasses javascript and php/mysql and might even stretch to AJAX if i get some real enthusastic responses. i have two mysql tables, one called CATEGORIES and one called SUBS (sub-categories). i have two drop down boxes on my page, each one to be populated by the aforementioned table data respectively. how can i dynamically populate the SUBS listbox with the joined data to the CATEGORIES listbox I.e. -------------------------------------------------- CATEGORY home and garden SUB-CATEGORIES furniture, plants, interior design -------------------------------------------------- CATEGORY technology SUB-CATEGORIES mobile phones, computers, visual technology -------------------------------------------------- so when the main category is changed, the second listbox changes to accomodate joined information. any help is appreciated !!