The Madden-Julian Oscillation (MJO) is a fundamental mode of atmospheric variability in the Tropics that influences a number of important climate and weather phenomena (e.g., monsoon onsets and breaks, ENSO, hurricanes). As yet our global models are largely incapable of correctly simulating or predicting the MJO and a well-accepted theory is still illusive. To address this challenge, more emphasis is being placed on characterizing and understanding the vertical structure of the MJO. In this study, we utilize the constantly improving estimates of atmospheric latent heating provided by TRMM. Specifically, we utilize latent heating profile estimates from two different algorithm teams, along with heating estimate from ECMWF analyses, to describe the evolution and spatial variability of atmospheric latent heating associated with the MJO. This includes characterizing the contributions from deep convective, stratiform and shallow convective clouds, and put these in context of model shortcomings and other observations of the MJO vertical structure – such as water vapor and temperature from AIRS.