I am not a huge fan of customizing a résumé for every position one applies to (I think that time could be better spent networking) but I do think having one (possibly two) résumés that hit the major key words and key experiences of a functional area can be very beneficial.
One of my favorite new ways of doing this is to use a tool call Wordle, a tool for generating “word clouds” from text that the user provides. The cool thing here is that the more frequently a word appears in the text you provide the bigger it will appear in the picture that is produced.
If I was looking for a job today I could (and should and would) find several (10+) recruiting job descriptions from across the country from sites like Monster and CareerBuilder, put them into a tool like Wordle, get the results and then do the same with my résumé and compare the output (see below). If the same words are enlarged in both I could rest assured that my marketing document was hitting the mark, if not I would probably want to go adjust a few things.
Until next time, good hunting and good luck!