We review the recent empirical research assessing market power on the Nordic wholesale market for electricity, Nord Pool. The studies find no evidence of systematic exploitation of system level market power on Nord Pool. Local market power arising from transmission constraints seems to be more problematic in some price areas across the Nordic countries. Market power can manifest itself in a number of ways that have so far escaped empirical scrutiny. We discuss investment incentives, vertical integration and buyer power, as well as withholding of base-load (nuclear) capacity. (C) 2009 Elsevier Ltd. All rights reserved.