The past decade has witnessed tremendous progress in the wet-chemical preparation of semiconductor nanocrystals with defined size, shape, and surface chemistry, driven by their immensely promising fundamental and technical applications. [1] One current focus lies in establishing methodologies to synthesize one-dimensional (1D) nanostructures such as nanorods and nanowires owing to their increasingly recognized advantages over quasi-spherical nanocrystals, so-called quantum dots (QDs), particularly in view of technical applications. [2] Anisotropic crystal growth is a prerequisite for the formation of 1D nanostructures and necessitates a profound difference in the surface energy between crystallographic facets. [1] In this context, the hexagonal wurtzite structure is favored as a consequence of the large chemical dissimilarity of their facets as compared with the cubic zincblende structure. [1,3] To date, 1D nanostructures of various semiconductors have been generated in organic media mainly through decomposition of lipophilic organometallic precursors at high temperatures in the presence of two or more ligands. [4] Recently, high-quality QDs, particularly of type II/VI semiconductors, have been prepared in aqueous media with the aid of water-soluble thiol ligands. This method offers a number of advantages such as low cost, facility of scale-up, and being environmentally friendly. [5,6] The aqueous synthesis methodology, however, cannot be used to directly generate 1D nanostructures owing to temperature limitations; a crystal growth temperature of around 100 8C is not sufficient to overcome the energy barrier of transforming zinc-blende to wurtzite structures. Most recently, the groups of Kotov and Rogach reported success in transforming preformed zincblende QDs of CdTe into wurtzite nanowires by partially removing the capping ligands of thioglycolic acid (TGA). [7] Inspired by these successes, herein, we demonstrate the direct preparation of stable colloidal CdTe nanorods or nanowires in water (by storing dilute aqueous solutions of their precursors) which selectively occurs in the presence of ligands with a