"Time" has been appointed as a new source of Competitive Advantage (CA) and following this trend flexibility, that is deeply related to quick responses for changes in the environment, becomes a key element for CA Using survey data collected from 212 manufacturing companies in US, we investigate the importance of flexibility and Information Technology (IT) as major elements in achieving CA. We identify CA from performance measures related to market growth, market share and profitability. Flexibility is evaluated using manufacturing and product development perspectives, emphasizing changes in these two business functions. The study also looks at the relationship between the integration of Information Systems (IS) and introduction of Information Technology (IT), and key variables for CA The results support the hypothesis that flexibility is related to the measures of CA and show that IS/IT is primarily related to the service dimension