Research into mind-matter interactions (MMI) investigates the possibility of some sort of relationship between the consciousness of living beings and external material systems, mediated by mechanisms beyond those we presently understand. This paper presents a conceptual basis for experimental strategies in the investigation of such effects. Twelve different classes of interpretations of evidence are presented and described. An observer-centered communication model is developed for use in designing MMI experiments and its application described. It is linked to three kinds of ESP designs (restricted choice, free response and somatic) and three kinds of PK designs (discrete outcome, stable system and static system). Some measurement issues in MMI research are raised, relating to evaluation of the null hypothesis and the concept of psi-missing.