I attended the surprising birthday party for the wife of my co-worker, today. We Japanese don't have the culture to hold home parties except for birthday party for the children. So it was a chance to enjoy the home party in the UK. About fifteen people attended it; friends, relatives, and co-workers. He requested us to come his flat within a restricted time window. During the time window, one of their friend invited his wife to a cafe and keep her there. The other members came their flat during the time window. It was his plan and worked well. All of us prepared to set off firecrackers and waited her coming back. We let off them when she opened the door of the living room. She was so surprised. We enjoyed talking, drinking, and eating something. I was surprised that the party was not so organized; no programs and no facilitator except for the time when we let off the firecrackers and singing a birthday song. Each person talked, drunk, and ate in their own way. I noticed that it might be a home party! And I found that it was similar to the party held on the first day of an international academic conference. Although the parties in academic conferences are well organized, the party on the first day is not organized so much. I wondered it. The participants for international academic conferences come from far away and meet each other after ling time no see. So the party on the first day may have a elements of home party, I think. So the party on the first day is not so organized; like a home party. I got a glimpse of their culture.