What names to use for your boss, subordinates and co-workers at office.
For calling your boss or seniors at office, you are to use their title instead of his/her family name. For example, if you have a boss whose name is Mr. Suzuki and is a section manager, you are just to call him “Kacho (=Section manager)” or “Suzuki Kacho” in office.
For calling your subordinates or co-workers, you are to use their family name with -san.
For example, if you have a co-worker whose name is Mr.Tanaka, you are to call him “Tanaka-san”. Seniors sometimes use -kun” for calling male subordinates, like “Tanaka-kun”. Since Japanese people have difficulty in pronouncing foreign family names, first name with–san is often used for foreign workers, for example, Cathy-san” is for the person named Catharine.
Names to use when talking with your clients or people outside the company.
If you need to mention the name of your boss or co-worker in a business talk with people out side of your company, you are to use his/her family name, without –sun. If you have a boss whose name is Mr. Suzuki, you are to use just “Suzuki”, in the business talk, for example, “Regarding the contract, Suzuki (of our company) reviewed and…..” or “契約につきましては、うちの鈴木が検討し、・・・“etc.
Names to use for clients or seniors
For calling your clients or seniors, use his/her family name with –sama instead of -san. –sama is much formal than sama. Using –san is rather rude for clients, and should be avoided.
For politicians, lawyers or consultants, we use “Sensei” instead of “san”, for example “Suzuki-sensei”. Basically, “Sensei” basically used for teacher.