Recent advances@footnote 1@ in the field of carrier-controlled ferromagnetism in tetrahedrally coordinated diluted magnetic semiconductors and their nanostructures will be reviewed with a focus on the phenomena important for prospective spintronic devices. Experimental results for III-V materials, where the Mn atoms introduce both spins and holes, will be compared to the case of II-VI compounds, in which the Curie temperatures T@sub C@ above 1 K have been observed for the uniformly and modulation-doped p-type structures but not in the case of n-type films. The experiments demonstrating the tunability of T@sub C@ by electrostatic gates as well as by light will be presented. The tailoring of domain structures and magnetic anisotropy by strain engineering and confinement will be discussed emphasizing the role of the spin-orbit coupling in the valence band. The question of designing modulated magnetic structures in low dimensional semiconductor systems will be addressed. Recent progress in search for semiconductors with T@sub C@ above room temperature and hopes associated with materials containing magnetic ions other than Mn will be presented. @FootnoteText@ @footnote 1@ T. Dietl, H. Ohno, F. Matsukura, J. Cibert, and D. Ferrand, Science 287, 1019 (2000); H. Ohno et al., Nature 408, 944 (2000); P. Kossaki et al., Physica E 6, 709 (2000); D. Ferrand et al., Phys. Rev. B 63, 085201 (2001); T. Dietl, H. Ohno, and F. Matsukura, Phys. Rev. B 63, 195205 (2001).