IntroductionNitrogen-containing compounds are ubiquitous and are extremely important in synthesis. This chapter reports some general aspects of the generation, structure, and reactivity of nitrogen-bearing organolithiums showing the progress made over the last decade. The chapter does not cover comprehensively the field but the aim is to provide the reader with useful information on the generation, reactivity, and potential in synthesis of this kind of lithiated intermediates.Throughout the chapter, the name amino-organolithiums is used to describe reactive intermediates lithiated at sp 3 -hybridized carbon atoms adjacent (α) to a nitrogen atom that could be included also in a ring. Amino-organolithiums can be generated mainly in three different ways: (i) deprotonation of a parent amine or its derivative; (ii) transmetallation by using an alkyllithium; and (iii) reductive cleavage of C-heteroatom bond (e.g., C-S). Each way has advantages and disadvantages and in some cases they complement each other (Scheme 7.1).Direct deprotonation is a widely used strategy to generate amino-organolithiums even in chiral form, while tin-lithium exchange reactions are preferred when direct deprotonations are difficult (high kinetic barrier) or regiochemical issues apply. Concerning the direct deprotonation of amines, this is not a simple task because the corresponding lithiated intermediates suffer from destabilizing interactions that make this reaction very difficult unless a ''stabilizing group'' (SG) is introduced either on the nitrogen atom or on the lithium-bearing carbon (Scheme 7.2).The SG (Scheme 7.2) has a pivotal role, either reducing the kinetic barrier in the hydrogen/lithium permutation or stabilizing the organolithium mesomerically or by coordination. For these reasons, often, amino-organolithiums are classified as stabilized or unstabilized. The chemistry of unstabilized amino-organolithiums has been so far less developed however, lithiation of simple tertiary amines could be accomplished by two main strategies: (i) by tin/lithium exchange reaction and (ii) by deprotonation of quaternary ammonium complexes (Scheme 7.3).