The purpose of this joint workshop is to enable different expert research teams to compare approaches for modelling populations of a range of northern phocid species with similar life histories, focusing on species for which abundance estimates are fundamentally based on pup counts. The genesis for this workshop was a recommendation in 2019 by the ICES/NAFO/NAMMCO Working Group on Harp and Hooded Seals (WGHARP), who recommended that ICES and/or NAMMCO convene a workshop on population assessment models for seals in the North Atlantic to advance model development with respect to uncertainty in fecundity and other input parameters. Techniques developed in this workshop will help inform future ICES benchmark meetings intended to review and improve assessment methodology.