Abstract
One of the primary responsibilities of the neuronal growth cone is its role of guiding an elongating neurite to its proper target. The events during extension and pathfinding require that the neuronal growth cone responds to particular molccules in the environment by making appropriate changes in the behaviour of the growth cone. This paper discusses the role of intracellular calcium as a signalling system mediating these responses. The specific roles of the growth cone lilopodia in acting as antennae in advance of the motile growth cone are discussed in the context of calcium mediated pathfinding events.