Sourcing refers to finding job candidates though using recruiting techniques. The actual act of discovering candidates is performed by either an internal recruiter, agency, or a designated sourcing professional (referred to as a sourcer).

Candidate sourcing activity usually ends when all of the information for a potential employee is received by the candidate sourcer. To further develop potential employees, companies will sometimes have a second person contact the people on the list to pre-screen the candidate based on the job requirements and determining the interest level in hearing about new job opportunities. This is called "Candidate Profiling" or "Candidate Pre-Screening".

Websites specifically used for candidate sourcing include: LinkedIn, Facebook, Twitter, internal ATS/CRM systems, ZoomInfo, Google, and large job boards such as Monster, Careerbuilder, and Indeed. Networking is a primary discipline of an aggressive recruiter; each contact should be considered the point under-which lies a network of related contacts. Sourcing professionals use one contact as leverage to discover the list of related industry contacts. By doing this, sourcers generate large lists of potential candidates for which to further profile and interview.