This book addresses the realization of pronominal subjects in Bulgarian and its implications for late near-native competence of German as a second/foreign language. Since Bulgarian is under-researched, typological investigations were carried out prior to the empirical study of L2 subject use. The book covers the adequate classification of Bulgarian, ascertaining its pro-drop nature, and explores the possible impact of related cross-linguistic differences on near-native interlanguage grammars of speakers with the language combination L1-Bulgarian/L2-German. Although German is not pro-drop, it allows null topics and requires some obligatory null expletives, so that null subject contexts superficially overlap for the two languages. This is a source of interlanguage deficits if no proper differentiation between subject types is made.