Current developments in opto uidics are concentrated around three major themes: (1) optical devices with functionality de ned and controlled by uids, (2) optical detection of particles in chip-scale uidic environments for chemical or biological sensing, and (3) optical manipulation of micro-and nanoscale particles. ese trends are not only apparent from a look at the scienti c l iterature and topical conferences (IEEE summer Topical Meetings 2006 and 2008, CLEO conference 2009), they are also re ected throughout the various chapters of this book. e main bene ts of these e orts are to create novel optical devices with highly tunable properties and to translate well-established microscopy-based methods to a lab-on-chip environment with all its advantages for uidic analysis.