During 5-7 September 1990, the Scientific Council held a Special Session on "Management Under Uncertainties Related to Biology and Assessments, with Case Studies on Some North Atlantic Fisheries" at the Lord Nelson Hotel, Halifax, Nova Scotia, Canada, with J. Shepherd (EEC-UK) as convener. Keen interest in the contributions and associated discussions prompted the Scientific Council to consider publishing all contributions in a single volume of NAFO Scientific Council Studies. Of the 22 presentations made at the Session, 16 papers and 5 extended abstracts were accepted for publication in this issue of Studies after review by the convener and the editor. The contributions are printed in the order they were presented at the Session.

During 5-7 September 1984, the special session on "Biology and Ecology of Squids in the Northwest Atlantic" was held at the Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada, with T. W. Rowell (Canada) and Ch, M. Nigmatullin (USSR) as conveners. Keen interest in the contributions and associated discussion prompted the participants to propose that the Scientific Council consider publishing all suitable papers in a single volume.

Of the 27 documented contributions, 15 papers and a bibliography were accepted for publication in this issue of Studies after critical review by one or both conveners and the editor, with the occasional assistance of other fishery scientists. The titles and available abstracts of the remaining 11 contributions, which were either not submitted or not suitable for inclusion in this volume, are listed on pages 171-175.