This article analyses the emerging European regulatory activities in relation to nanopharmaceuticals. The central question is whether the regulatory responses are appropriate to cope with the regulatory problems nanomedicinal development is posing. The article explores whether the medical product regulations are robust enough, whether there are certain regulatory gaps, and whether the competent bodies have the expertise to evaluate nanomedicinal products when approval is applied for. Based on a social-constructive approach, the article identifies significant regulatory actors, their ideas on regulatory problems, and preliminary governance responses to them. It finds that the current dynamic regulatory structure appears robust enough to adapt to some of the technological challenges posed by nanomedicines. It concludes that regulators have not yet responded adequately to regulatory gaps related to definitions, classification and specific safety, quality, and efficacy standards that nanopharmaceutical development seems to require. As a consequence of these deficiencies legal certainty, a principle of high priority in European medical regulation policy, cannot be sufficiently provided.