In business, “sama,” “san,” or an official job title is added after a surname, but in casual situations this can create a sense of distance between speakers. In casual situations, “san,” “chan” and “kun” are commonly used. If you add this to a first name when addressing a person, it creates a feeling of intimacy. Out of these “san” is standard. Since it’s not too polite, nor too casual, it’s best to use “san” when you’re not sure which is correct. “Chan” is added after a first name and is used for both boys and girls. In addition, it is also used by close friends to address adult women. “Kun” is added after a first name or family name, and is used to address boys. You may also use it with male colleagues and male friends of your own age or younger. In the event that you address someone by their name without using an honorific, if you use their surname this would be taken to mean that you are disrespecting them and if you use their first name this might indicate that the person is your spouse or sweetheart. However, as it is known that it is common practice to address people by their first name in the West, many Japanese don’t mind if westerners call them by their first name. However, men who are close friends do call each other by their surnames without attaching an honorific. Even closer friends are more likely to use nicknames or first names only. Standard polite conversation: Model Dialogue for Business: in this case you are introducing somebody from a partner company and a junior colleague to your host. A: This is Kazuo TANAKA, department chief of XX Company. B: Mr. TANAKA, welcome. A: Next to him is my junior colleague. B: Ms. Satou, how do you do? Casual expressions: In this case you are in a izakaya (bar) introducing your friends to your host.