Understanding intention of businesses to adopt e-commerce is important for researchers and firms. This can be studied with different research strategies and from different angles. The current study is conducted on business-to-business (B2B) e-commerce adoption at firm level from business- to-business relationship angle. The respondents were asked to idnentify, validate and assess the importance of attributes identified effective in B2B relationships. The second part of this study investigates the impacts of adoption of e-commerce on B2B relationships. Three different relationships are used to validate the findings of the collected data by applying PROMETHEE. The results are showing that B2B e-commerce will have certain impacts, obviously with different magnitudes, on the relationship of businesses with each other. It could guide businesses on how to prioritize their e-commerce projects roll out in B2B context as well as maximize their investments on their relationships, deploy an effective B2B e-commerce and increase their B2B relationships efficiency by enabling electronic aspects in their relationships.