The EMBO workshop on ‘Meiotic Divisions and Checkpoints’ was organized by C. Jessus, M.H. Verlhac, T. Hunt and A. Nebreda and took place in Cargese, France, between 16 and 20 March 2005. ![][1] Meiosis is a special type of cell division through which haploid gametes are generated from diploid parent cells. This is accomplished by a first division that induces homologous chromosome segregation followed by a second mitosis‐like division that promotes sister chromatid separation. During the prophase of meiosis I, three basic events take place: pairing of homologous chromosomes, synapsis and recombination. Pairing or alignment of homologous chromosomes allows chromosome stabilization by the formation of the synaptonemal complex, whereas synapsis facilitates the subsequent recombination events. The synaptonemal complex is a proteinaceous structure formed by lateral elements and transverse filaments (Fig 1; Page & Hawley, 2004). The lateral elements comprises cohesins (Rec8/C(2)M/SYN1, STAG3/Rec11, SMC1‐b and SMC3), the structural proteins SCP2 and SCP3, and the HORMA‐domain proteins Hop1/HIM3/Asy1 and Red1; the transverse filaments are formed by the proteins Zip1, SCP1, C(3)G and SYP1. Once the synaptonemal complex is assembled, crossover recombination events take place between homologous partners. Crossovers form temporary connections or chiasmata that hold homologues together and allow their correct attachment to the meiosis I spindle. However, in most vertebrate oocytes, spindle I formation and germinal vesicle breakdown (GVBD) is preceded by an arrest at prophase I. This arrest is maintained until progesterone stimulates re‐entry into the meiotic cycle by inducing the polyadenylation and translation of several dormant mRNAs that encode proteins such as Mos or cyclin B. Translation of Mos and cyclin B activates the maturation‐promoting factor (MPF) and thereby induces spindle formation and GVBD. Homologous chromosomes then attach to the spindle and when aligned correctly along the metaphase plate, they segregate—a process that in some species is regulated, at … [1]: /embed/graphic-1.gif