  Wide parameter space searches for long lived continuous gravitational wave
signals are computationally limited. It is therefore critically important that
available computational resources are used rationally. In this paper we
consider directed searches, i.e. targets for which the sky position is known
accurately but the frequency and spindown parameters are completely unknown.
Given a list of such potential astrophysical targets, we therefore need to
prioritize. On which target(s) should we spend scarce computing resources? What
parameter space region in frequency and spindown should we search? Finally,
what is the optimal search set-up that we should use? In this paper we present
a general framework that allows to solve all three of these problems. This
framework is based on maximizing the probability of making a detection subject
to a constraint on the maximum available computational cost. We illustrate the
method for a simplified problem.
