I can only recommend Delengua. Whether you want to improve your Spanish before going on a Holiday or for professional reasons – they will surely be able to offer you what you need. Classes are taught in small groups, are fun and interesting. The teachers are very good at putting people with the same Spanish level together, something I was worried about. During the amazing activities the school organises in the evening (during which everybody continues to speak Spanish) you get to know most of the teachers and the students (all age groups). This results in lots of greetings in the hallways during the day and a family-like atmosphere. The members of the back-office are always available and react quickly to any requests via mail or phone. During my 3 week stay, I stayed in one of their apartments which was right above the school. It was clean and offered everything I needed. I will definitely come back.