Human Capital Institute (HCI) has produced an interesting report/survey on the issue of contractors in talent management initiatives (see here for report). They conclude that procurement and selection of contract talent (CT) should be centralized in HR and the strategy around CT should be aligned with the general Talent Management Program.
The background for the study is the fact that most organizations has a huge gap between how they manage their contractors and their strategic needs for competencies.
One of the problems is that it is not always (sometimes rarely) that HR is even involved in hiring and administering contractors. A study showed that it was only the case in 50% of cases. Most of the times it is from the business units themselves. This ownership issue is a problem.
But should contractors be part of a talent management? Well, I think it depends on how you define it. It think contractors should be administred from HR and should form part of the overall Human Capital strategy. Contractors is an important part of the overall workforce planning tool and issues about who and what competencies should be hired are important strategic HR decisions. But from there to be included in a talent management strategy? I am not sure it make sense.