In Japan, the idea that "Harmony is the greatest of virtues" is still very much alive in the business world. A typical expression related to that spirit is o-kage sama de, which means "thanks to ~." It's used in examples like "Thanks to you, we could get the contract." Even though you may actually have done most of the work, by using the expression o-kage sama de to express your appreciation of everyone's guidance and support, you can show that you value their cooperation highly.
On the other hand, if you start off by saying Zannen nagara... meaning "Unluckily..." or "Unfortunately...," it indicates you're about to report some bad news.
Ossharu tôri desu ga... means "It's just as you say, but..." It's used when you present a counter-opinion, implying the nuance of "I fully understand what you want to say, but..."
When you can freely use these expressions, you can be considered as a fully-fledged worker in Japan!
