Depends on the actual school and the instructors I think. In my Muay Thai Camp what generally happens is there are 5 introductory classes for beginners that is mandatory for the beginner to attend before moving in to the regular class. So basically, during the class the beginners join the regular group to go through the regular warmup training part of the class which involves a very high intensity combination of cardio and strength conditioning exercises. When the muay thai instruction part starts, the beginners are then taken aside and taught the basics. They do this for 5 classes. After that it is mandatory to have the gloves and required gear for the regular classes. Yes you are right, some people have been there longer but generally it does not affect anything unless you go into more advanced classes like sparring classes. In my training camp it is designed that there are several beginner level classes all week long 5 nights a week. There are also mixed level regular muay thai classes during the day time and also mixed level classes on the weekends. There are also advanced classes and sparring classes that take place all week long. There are more then enough classes to choose from as you advance. Depends on what you wish to do with muay thai? Do you plan to compete? If so you will be training very hard. The majority of the people that attend my camp do so for the health benefit one gets from the intense workouts. Also the majority of people do not go to be graded and usually end up remaining in the regular muay thai classes as they only seek the benefit of gettting in shape. As far as going up levels there is an opportunity to test your skills to advance every 3 months or so, that does not mean you test every 3 months, that means there is an opportunity to test every 3 months, you only test when you think you are ready and wanting to advance. But as I said most people there stay at the beginner level as they have no intention of competing. It all comes down to what you want from muay thai. Alot of it also depends on the instructors and the gym you attend and the way the classes are designed for training. No harm to go and ask questions; if it is a decent muay thai camp they should allow you to participate free for one beginner class so you can see whether or not muay thai is for you. But I will tell you based on my camp that muay thai is definitely a very intense workout that will no doubt get you in shape and also the added feature of self defence. I find my camp/gym to be awesome and I am greatful to be learning muay thai and getting in good shape at the same time. Best wishes, but do not be intimidated by those who might be advanced in the same class. More often then not you will find those who are more advanced in your class to be good comrades inspiring you to achieve your goals. They had to advance somehow right? they were once beginners also. Sometimes there are people that are more advanced in my classes, does not make a difference as we practice what the ajarn instructs, the more advanced person might have better technique thats about all but people are generally pretty decent when it comes to new people and I find it to be a very positive environment, people are usually helpful and will not look down on you in the least if you are new, if anything they will try to help you be the best you can be to achieve your goals with muay thai. Best wishes