Book excerpt: This dissertation discusses advancements in open channel microfluidics, the design and fabrication of open channels and capillary pumps, and methods to manipulate open channels. An open droplet-based microfluidics platform is demonstrated with promising future applications. Additionally, an expression to measure the velocity of capillary flow in an open channel and design guidelines for an efficient capillary pump are presented.Chapter 1 discusses the field of microfluidics and the advantages of such platforms. The fundamentals of open microfluidics is presented along with the benefits of open channel systems. Capillary flow is discussed, and the necessary considerations for fabrication of channels to ensure that the fluid in the system is driven by capillary means is provided. Droplet-based microfluidics is a large subfield of microfluidics, which is briefly reviewed, and a need for further fundamental and applied work using droplet-based systems which are completely driven by capillary flow is discussed. Finally, capillary pumps provide a solution to the inherent decrease of velocity (and flow rate) observed in channels driven by capillary flow. Chapter 2 introduces droplet-based microfluidics where droplets are formed in an open channel that is completely driven by capillary means. Our work represents the first time that this phenomenon was observed and studied. The interaction that exists between a droplet and the surrounding phase is described in detail. Chapter 3 explores fundamental microfluidic features in open channels: droplet splitting, multiple droplets, and droplet merging. An example of an open platform that enables users to manipulate droplets on the same chip is presented. Chapter 4 investigates capillary flow in an open channel, and an expression to measure velocity derived from the Lucas-Washburn-Rideal law is presented. The capillary flow in bifurcations and networks of open channels are studied. Chapter 5 investigates the theory of open capillary pumps to alleviate the inherent decrease of velocity and flow rate during capillary flow. Design guidelines of an efficient open capillary pump are discussed. Chapter 6 concludes the thesis with an overall perspective of the field and other experimental proposals to improve the overall design of open channels and capillary pumps and to enable applications with the platform.