Basic reproductive data from 21 green turtle (Chelonia mydas), 8 leatherback (Dermochelys coriacea), 7 hawksbill (Eretmochelys imbricata), 7 olive ridley (Lepidochelys olivacea),6 loggerhead (Caretta caretta), 1 Kemp's ridley (Lepidochelys kempi), and 1 flatback (Chelonia depressa) populations are provided. Some intraspecific and interspecific relationships between size of nester and clutch, egg size and hatchling size are analyzed. Measurements of reproductive rates (=numbers of hatchlings per female per year) in 11 populations varied from 35 to 200 in an olive ridley and loggerhead colony, respectively. Nesting behavior of each species is described in terms of type of nesting emergence and time spent on the nesting beach (=chelonery). The relatively large number of yolkless eggs laid by many leatherbacks and by some hawksbills invites further study. Some aspects of sea turtle nesting behavior and reproduction are compared to those of other chelonians.