Conservation biological control is commonly considered to be a key component of IPM because it is compatible with and complementary to many other approaches available in the IPM ‘toolbox’. However, despite significant study of conservation biological approaches in horticultural systems, uptake has been limited. Furthermore, whilst there are many studies that provide examples of positive implementations, there are as many studies in which the evidence for benefits to pest control is either inconsistent or absent. We suggest that careful consideration needs to be given to the scale at which studies of conservation biological control are conducted (both spatial and temporal) and the metrics that are recorded. To-date there has been a bias towards ecological studies, with relatively scant consideration of the economic impacts of conservation biological control measures. We propose a framework for the future study of conservation biological control approaches, which centres around economic costs and benefits.