Advances in software process technology have rendered some existing methods of size assessment and effort estimation inapplicable. The use of automation in the software process, however, provides an opportunity for the development of more appropriate software size-based effort estimation models. A specification-based size assessment method has therefore been developed and tested in relation to process effort on a preliminary set of systems. The results of the analysis confirm the assertion that, within the automated environment class, specification size indicators (that may be automatically and objectively derived) are strongly related to process effort requirements.