The 2014 workshop on medical computer vision (MCV): algorithms for big data took place in Cambridge, MA, USA in connection with MICCAI (Medical Image Computing for Computer Assisted Intervention). It is the fourth MICCAI MCV workshop after those held in 2010, 2012 and 2013 with another edition held at CVPR 2012. This workshop aims at exploring the use of modern computer vision technology in tasks such as automatic segmentation and registration, localisation of anatomical features and extraction of meaningful visual features. It emphasises questions of harvesting, organising and learning from large-scale medical imaging data sets and general-purpose automatic understanding of medical images. The workshop is especially interested in modern, scalable and efficient algorithms which generalise well to previously unseen images.The strong participation in the workshop of over 80 persons shows the importance of and interest in Medical Computer Vision. This overview article describes the papers presented in the workshop as either oral presentations or short presentations and posters. It also describes the invited talks and the results of the VISCERAL session in the workshop on the use of big data in medical imaging.