Meditation Volume 2 forms a link to the accounts of experience detailed in Volume 1 and operationalizes them for empirical research. The first two chapters summarize the vast number of empirical studies - several hundred - and divides them into physiological and mental correlatives. The studies relate to in-patients, the workplace, normal test persons, higher states of consciousness, negative results, side-effects and prognostic factors of meditation. The third chapter treats of theoretical models, followed by a section on measuring instruments. The appendix introduces a research project.