This is an innovative and distinctive comparative monograph about new word creation in the different varieties of Catalan. In eight chapters, it provides a panoramic analysis of the neologisms documented by the NEOXOC network. Each chapter is dedicated to the qualitative and quantitative analysis, as well as the comparative territorial analysis, of neologisms, differentiated by formation sources: suffixation, prefixation, neoclassical compounding, vernacular compounding and syntagmatic compounding, Spanish loanwords, English loanwords, truncation and semantic change. Two annexes contain the neologisms cited as well as a sample of the data collected by NEOXOC from a corpus during 2008-2010, thus establishing a link with previous studies carried out by the Observatori de Neologia. The innovative approach (based on the analysis of diatopic variation in Catalan lexical neology) makes it relevant for those who are interested in the evolution of languages, linguistic variation and language planning. The chapters are written in Catalan, with extensive English summaries.