LinkedIn remains the most popular site for recruiting and screening candidates.  SHRM released new research showing organizations are increasingly using social networking sites to recruit job candidates.  77 percent of respondents use social networking sites to recruit candidates, which is up from 56 percent in 2011.  Interestingly, 57 percent do NOT have any kind of policy — formal or informal — for using social networking sites to screen candidates.  Insert red flag here!  A major reason respondents said they do not use or are cautious about using social networking sites is legal concerns of discovering information about protected characteristics, such as age.  The practice will undoubtedly continue and issues of relevance, effectiveness, legality, validity and cost are new frontiers for Employment Managers.  (Information gleaned from April 23, 2013 SHRM Weekly News.)