We present a system of programs designed to facilitate sequence analysis projects involving large amounts of data. SEALS (System for Easy Analysis of Lots of Sequences) is a logically organized set of flexible, easily modifiable research tools, designed to run on open systems. Functionality is divided into approximately 50 commands which follow consistent syntax and semantics; wrappers are also provided for commonly used sequence analysis software to effect similar syntax for these programs. SEALS includes software for retrieving sequence information, scripting database search tools such as BLAST and MoST, viewing and analyzing search outputs, searching in and processing nucleotide and protein sequences using regular expressions, and constructing rational predictions of protein features. The system is designed to provide modular elements which can be combined, modified, and integrated with other methods in order to quickly design and execute computer experiments for sequence analysis projects at the scale of whole genomes.