A fairly recent development in the WEKA software has been the addition of algorithms for multi-instance classification, in particular, methods for ensemble learning. Ensemble classification is a well-known approach for obtaining highly accurate classifiers for single-instance data. This talk will first discuss how randomisation can be applied to multi-instance data by adapting Blockeel et al.'s multi-instance tree inducer to form an ensemble classifier, and then investigate how Maron's diverse density learning method can be used as a weak classifier to form an ensemble using boosting. Experimental results show the benefit of ensemble learning in both cases.