Data from plant breeding trials need to be analyzed properly, with greater speed to support selection decision making. Genetic information should also be derived from breeding trials to determine more efficient breeding strategies. Although general statistical software can be used to analyze breeding trials, many practical breeders are seeking easy-to-use analytical tools. A software for plant breeders, PBTools, is being developed at IRRI. It is a free application, created using the Eclipse Rich Client Platform (RCP) and R language and has a user-friendly graphical user interface (GUI). The current version provides modules for analyzing single- and multi-environment trials (METs) conducted using widely-used experimental designs. Genotype can be regarded as fixed or random effect. Depending on the model, the outputs include ANOVA table, variance components, heritability and pairwise comparisons. For METs, the regression-based stability parameter and Shukla’s stability variance are also computed and, the Additive Main Effects and Multiplicative Interaction (AMMI) model is implemented. In the future, modules for generating design layouts, breeding value prediction based on genetic relationships between genotypes and multi-trait selection index will also be included.