The International Maize and Wheat Improvement Center (CIMMYT) recently published "Doubled haploid technology in maize breeding: Theory and practice", edited by B.M. Prasanna, V. Chaikam and G. Mahuku. This 51-page manual is primarily intended for maize breeders in the national agricultural research systems and small and medium enterprise seed companies in developing countries who would like to better understand and use the doubled haploid (DH) technology in breeding programs. It is a compilation and consolidation of knowledge accumulated through scientific contributions of several maize geneticists and breeders worldwide as well as protocols successfully developed (in collaboration with the University of Hohenheim, Germany) and used by the CIMMYT Global Maize Program in DH line development, especially in Mexico. See http://repository.cimmyt.org/xmlui/bitstream/handle/10883/1351/97066.pdf (2.8 MB) or contact [email protected] for further details.