This paper has two main objectives: (a) to put the vast body of research on Swedish as asecond language (SSL) into one coherent framework; and (b) to test the predictions derivingfrom processability theory (Pienemann, 1998a, 1998b) for Swedish against this empiricaldatabase. We will survey the 14 most prominent research projects on SSL covering wide areas ofsyntax and morphology in longitudinal and cross-sectional studies. This survey is the first to becarried out for Swedish, and it will bring the body of two decades of research into one unifiedframework. We proceed in the following steps: First, a brief summary of processability theory isgiven. Then the theory is used to generate a unifying framework for the development of thespecific L2 grammatical system (Swedish). Finally, the new framework is tested in theabove-mentioned empirical studies.