The topic of my dissertation is a domain of Dutch word formation which has so far been ignored in the morphological literature: the formation of complex adverbs through derivation. In overviews of Dutch word formation we usually find a list of suffixes for adverb formation: -(e)lijk, -(e)lings, -gewijs, -erwijs, -halve, -iter, -tjes, -waarts, -weg. These Dutch adverbial suffixes have only been treated very superficially which is in strong contrast with the genetically related German adverbial suffixes. Descriptions are usually restricted to the enumeration of a number of synchronic properties without empirical foundation. The diachrony of these suffixes has also remained in the dark whereas there are detailed diachronic descriptions of the German counterparts. With my dissertation I aim to fill these gaps by offering a detailed description of the Dutch adverbial suffixes from a synchronic and a diachronic perspective. It is based on qualitative investigation of attested language data from corpora and dictionaries. Two further word-formation morphemes are included, -matig and -technisch, whose German equivalents -mäßig and -technisch have recently received much attention in the literature. In view of the combined synchronic and diachronic perspective, I describe the development of each suffix starting in the oldest phase of Dutch until contemporary Dutch. Contrastive observations on German and English related suffixes are included to enrich the description of the Dutch suffixes. This dissertation contains three main parts. The theoretical and practical foundation of my study is provided in the first part (chapters 1-6). The second part is the core of the dissertation: chapters 7-17 represent descriptions of the Dutch suffixes -(e)lijk, -(e)lings, -gewijs, -erwijs, -halve, -iter, -matig, -technisch, -tjes, -waarts, -weg. Each chapter consists of an introduction, a synchronic description, a diachronic description and a conclusion. Finally, in the third part of the dissertation (chapter 18), the results of the ...