With the use of multiple medications in the elderly patient comes the risk of drug-related problems. This issue covers polypharmacy in the elderly patient with topics that include: The Interplay between Polypharmacy, Geriatric Conditions, and Adverse Drug Reactions, Factors Leading to Excessive Polypharmacy, Clinical Practice Guidelines for Chronic Diseases and How They Contribute to Polypharmacy, Polypharmacy in Nursing Home Residents, Psychotropic Polypharmacy, Deprescribing Trials: Methods to Reduce Polypharmacy and the Impact on Prescribing and Clinical Outcomes, Ethical Framework for Medication Discontinuation in Nursing Home Residents with Limited Life Expectancy, Pharmacokinetics in the Elderly and the Interaction with Polypharmacy, Medication Adherence to Multi-drug Regimens, Improvements in Electronic Prescribing to Reduce Inappropriate Medication Use and Polypharmacy, and Tools to Decrease Polypharmacy.