A study of zero-point vacancy effects in quantum solids using magnetic techniques developed under previous grant periods will be made. Measurements of zero-point vacancy effects are based on recent evidence that magnetic polarons may form around ground state vacancies in solid 3He. Quantitative results will be sought through measurements of magnetization and pressure as functions of density, applied magnetic field, temperature, impurity concentration, and sample geometry. The results will be analyzed and compared with theoretical calculations that remove some deficiencies of existing polaron models and with predictions based on improved stability criteria of polarons in the paramagnetic phase.