3-D printing technologies refers to the creation of objects from digital files based on a layer-by-layer or drop-by-drop approach. Our team aims to take advantage of this emerging technology to improve pharmaceutical products. Specifically, we have designed 3-D printed tablets containing two model drugs to be released alternatively. Based on mass transfer principles, the release profile of the 3-D printed tablets will be engineered by controlling the local composition of each drug during printing. Such a design will eliminate the need for the patients to take different drugs at different times, thereby reducing the pill burden and improving medication adherence. 3-D printing also comes with other benefits such as personalized medication, minimal drug waste, and drug abuse prevention. Our project demonstrates how 3-D printing technology can revolutionize the relationship between the pharmaceutical industry and patients.