The purpose of this thesis is to assess and compare the energy consumption and carbon footprints of two, online and offline, major movie rental services in Canada. The thesis is divided into two parts that represent two papers that are being published. The comprehensive literature survey provides the state-of-the-art in E-Commerce carbon footprinting with a new categorization framework. The model development and application compares the energy consumption and carbon footprints of the two business models via a systems approach and the Economic Input Output Life Cycle Assessment (EIO-LCA) model and evaluates environmental performances. The portions of the logistics chains that were different in the two business models were analyzed and processes that were common were excluded. Regarding findings, the analyses conclude that the online movie rental service has lower carbon footprint than the offline one. We suggest practical implications for policy makers, government, businesses, and customers in movie rental industry. / This thesis contains two papers, recently presented at international conferences and accepted for publication in recognized journals.