The book "Latent Variable Analysis and Signal Separation" documents the proceedings of the 14th International Conference on Latent Variable Analysis and Signal Separation, which took place in July 2018 in Guildford, United Kingdom. It includes 52 carefully selected and peer-reviewed contributions from 62 submitted papers. The research topics covered span a wide range, encompassing both general mixture models of latent variables and theories and tools from various disciplines. These include structured tensor decompositions, matrix and tensor factorizations, independent component analysis (ICA) methods, nonlinear mixtures, audio data and methods, as well as evaluation campaigns for signal separation. Additionally, advancements in phase reconstruction, sparsity-related methods, and applications in the field of biomedical data are addressed.