I specialize in algorithms (procedures for doing computations) and data structures (how to organize data so that algorithms can process them efficiently). Usually, I focus on algorithms that process geometric data or geometric networks, such as found in geographic information systems—this also leads me to study mathematical properties of tessellations and space-filling curves. Sometimes the goal of my algorithm design work is that a computer constructs a representation of the data, efficiently and correctly, that is optimized for efficient interpretation by humans.