The Manual of Immunological Methods represents the collaboration of the Canadian Network of Toxicology Centers, a non-profit network of university-based scientists dedicated to research, training, risk assessment, and communication. This manual provides detailed immunological methods that can be utilized by researchers or practitioners who want to enhance the successful application of this science. It emphasizes the need for continuously improving the quality of experiments performed and maintaining consistency in the results obtained. The Manual of Immunological Methods presents validated assays that are accompanied by a series of tools that will guide readers in performing their own laboratory work in the spirit of the Good Laboratory Practices. It covers specific methodologies including sample collection, preparation of cells, assay conditions, and data evaluation. Discussion of species differences and comparisons of a wide variety of species is an important feature. Both graduate students and practicing researchers in the areas of immunology and immunotoxicology will appreciate the Manual of Immunological Methods as a guide to standard operating procedures in the laboratory.