Recruitment. The mai problem (I have faced) is HR. Not just for the "people specs" others have raised, but for being overly involved in the process.
Couple of examples.
At One company, despite offering fantastic salaries, we were getting NO applicants. So I went direct to agencies. Lots of candidates. HR visited, asking me to stop. When I queried the lack of applications, I was told the "old" filter was as follows
This job will lead to an increase of >£5000 over current salary - bin.
CV not in company format (!!!) - bin
No experience in company market - bin
So HR had a new policy, complete with technical tests to filter candidates. Aye, they had tests. Thy had culled questions from the various tick tests offered by MS, Cisco, et al. My third line team tried the tests, and "failed"... because the exam-correct answers do not reflect real world answers, or in other cases were flat out wrong (sh int s0 being my favourite, followed by MS insistence that an MS Server build with more than one NIC MUST have IP routing enabled). I finally had two applicants... one was plainly using someone else's CV (asked how he would trouble shoot network level issues, replied "we plug into the black box"), the other claimed he didn't recognise the NMT software running on the workstation he was asked to demonstrate because he was "used to the Windows version".
Another company, potential managers were given a list of 15 skills/competencies, and asked to list them in terms of strongest to weakest. One candidate grouped them into 3 groups instead, strongest, strong, weakest. HR rejected him because they couldn't compare how his skills ranked against another... this despite the obvious flaw that, for example if one ranked "strategy, policy", and another "policy, strategy", he did not mean that the first candidates' strategy skills were stronger than the seconds, because it was a subjective self-assessment, not an objective measured test!
I could go on. But as we all know, there is no real skills shortage. Just a common-sense shortage at management level.