Position selection is a key task that must be carried out by a soccer-playing agent, but is often overlooked in favour of the more active tasks such as ball control. This paper examines the position selection implemented by the Essex Wizards team in the RoboCup Simulator league in recent competitions. The initial approach using task specific behaviours is firstly reviewed. The new approach is then addressed based on modular decomposition for flexibility. Implementation results are given to show the applicability.