This chapter discusses the relative importance of imaging technologies and the need to integrate information from multiple methods. It deals with several classes of computational techniques that allow the integration of data from magnetoencephalography (MEG) and magnetic resonance imaging (MRI) to improve the accuracy and reliability of functional neuroimaging by MEG. The chapter analyses the integrated application of two powerful paradigms for functional neuroimaging, exploiting the strengths and minimizing the weaknesses of each. Furthermore, it illustrates that because of the ambiguity associated with the neural electromagnetic inverse problem, a number of investigators have pursued the strategy of using fMRI to define the locations of activation while using MEG or EEG to estimate time-courses. Finally, the chapter mentions the need to expand the arsenal of methods available to the neuroscientist or physician for understanding the architecture and dynamic function of the human brain.