It has been our privilege to edit this volume which is complementary to the first book on Carbohydrate Metabolism in Pregnancy and the Newborn and which is based on work presented at the 2nd Aberdeen Colloquium bearing the same title held in April, 1978. The growth of knowledge of this subject in the 5-year period since the 1st Aber- deen Colloquium in 1973 is truly remarkable and fully justifies this second exposition of current ideas in this field at the present time. For example, the 1973 meeting failed to cover such recent to- pics as H. L. A. typing, glycosylated haemoglobin, control of glycae- mia in labour with the use of the artificial pancreas, fetal brea- thing and pregnancy specific B-glycoprotein and this volume provi- des such an opportunity. The scope of this book is broader and in- cludes data on placenta and fetal congenital anomaly related to ma- ternal diabetes and many aspects of birthweight while there is also a section on maternal weight and nutrition in pregnancy. In a wider prospective one of the stimuli for such work has been the impetus given by the regular meetings starting in 1969 of the Diabetic Preg- nancy Study Group of the European Association for the Study of Dia- betes. This has allowed much more effective integration of research on diabetic pregnancy. The work of the members of the Diabetic Preg- nency Study Group is widely represented in this publication.