This book provides a compact yet comprehensive overview of recentdevelopments in collisional-radiative (CR) modeling of laboratory andastrophysical plasmas. It describes advances across the entirefield, from basic considerations of model completeness to validation andverification of CR models to calculation of plasma kinetic characteristics andspectra in diverse plasmas. Various approaches to CR modeling are presented, together with numerousexamples of applications.  A number of important topics, such as atomicmodels for CR modeling, atomic data and its availability and quality, radiationtransport, non-Maxwellian effects on plasma emission, ionization potentiallowering, and verification and validation of CR models, are thoroughlyaddressed. Strong emphasis is placed on the most recent developments in thefield, such as XFEL spectroscopy. Written by leading international research scientists from a number ofkey laboratories, the book offers a timely summary of the most recent progress in this area. It will be a useful and practical guide for students andexperienced researchers working in plasma spectroscopy, spectra simulations,and related fields.