For a variety of reasons the activities performed by health care professionals are ever increasing, however the legislative process regulating these specialised workers is not keeping up with the practice realities. While competency statements and credentialling mechanisms are developing, they are not uniformly in place for specialists. Therefore activities completed by these practitioners may be legally controversial. This study documents a variety of tasks completed independently by nurses employed in three acute care hospitals that legally require medical orders and then examines the legal implications of this role extension. Credentialling is one mechanism by which nurses and other health care professionals can ensure they possess the levels of knowledge and skill required to perform the advanced activities required of them and consequently avoid negative legal repercussions.