I am an IT guy. I tried to improve my English by courses. As I understood later it was a wasting of money and (more importantly) time. The crucial moment was getting a job in Microsoft – foreign company with tens thousands employee. Then I realized that I still needed to improve my English. And not just common English but conversational English. My new colleagues advised me to learn English with native by (to save money) remotely. I tried Brown Cow English and have never regretted. Communicating with native. That is the key to success.