The MALSAR (Multi-tAsk Learning via StructurAl Regularization) package includes the following multi-task learning algorithms: Mean-Regularized Multi-Task Learning; Multi-Task Learning with Joint Feature Selection; Robust Multi-Task Feature Learning; Trace-Norm Regularized Multi-Task Learning; Alternating Structural Optimization; Incoherent Low-Rank and Sparse Learning; Robust Low-Rank Multi-Task Learning; Clustered Multi-Task Learning; Multi-Task Learning with Graph Structures; Disease Progression Models; Incomplete Multi-Source Fusion (iMSF); Multi-Stage Multi-Source Fusion; Multi-Task Clustering.