The power to appoint the head of an intelligence service under section 209(2) of the Constitution read with section 3(3)(a) of the Intelligence Services Act implies the power to dismiss, as this is necessary for the effective performance of the President's executive functions. The exercise of this power constitutes executive action under section 85(2)(e) of the Constitution, not administrative action subject to PAJA. While not subject to procedural fairness requirements as such, the exercise of the power to dismiss is constrained by the doctrine of legality, which requires that the decision be lawful, rational and not arbitrary. The irretrievable breakdown of the relationship of trust between the President and the head of the NIA, which is fundamental to the effective pursuit of national security, constitutes a lawful and rational basis for dismissing the head of the NIA. Where such dismissal occurs without fault on the part of the dismissed official, fairness requires that the official be placed in the same financial position they would have been in had the term run its course.