How to improve English Pronunciation?

I guess even if sometimes we are fluent in English we have problems in proper pronunciation of words which is very important in some aspects. Those who are trying better English Speaking might have a look to International Phonetic Alphabet http://en.wikipedia.org/wiki/International_Phonetic_Alphabet
This is very useful if you ever used English to English dictionary. You will find a word in the dictionary with the pronunciation sited beside. (e.g.   cup  /c^p/)
And learning new words with pronunciation would help properly speaking. IPA is a great tool to use while learning pronunciation. Hope this helps.