This chapter provides an in-depth overview of paper-based microfluidic devices (μPADs) and their fabrication, focusing on their significant role in advancing point-of-care and analytical applications. μPADs, designed for manipulating small fluid volumes, capitalize on the unique properties of paper—such as affordability, varied porosity, and capillary-driven fluid transport—to offer simple, portable, and cost-effective alternatives to traditional microfluidic devices made from glass or silicon. A discussion on the key aspects to be considered during fabrication is presented, along with an exploration of the paper’s application in analytical chemistry, highlighting the main detection techniques utilized in these devices.