It's a big field. I'd recommend staying away from "outside" recruiters (those recruiting firms who have only an affiliate relationship with the company who is hiring). "Internal" or "embedded" recruiters, on the other hand, might be the way a company prefers to be contacted. They, in some cases, are the defacto HR department for the company.<p>Generally, as a rule of thumb: If a recruiter reaches out to you and masks the company's name, then they are likely an outsider who is trying to protect their potential commissions (and trying to force you to work with them instead of circumventing them). These guys (and gals) are pretty much worthless bottom feeders, and have nothing of value to offer you. In fact, they might do damage by blasting your resume to every company in silicon valley without your permission! Run away!! On the other hand, if a recruiter reaches out with the company name, and encourages you to interact with the founders directly or come to an event, etc then they might be legitimate. This latter group can open doors or fast-track you through the HR process and might give you an advantage over applying directly.<p>In general, I like to ask "what benefit do I receive by working with you instead of applying directly?" If they say something along the lines of "Well, I can get you a lunch with the CTO this week." then that recruiter might be worth dealing with. It's all about the value-proposition. If they don't offer you one, then don't waste your time.