If there is one thing that can save all of us a lot of time, trouble and heartache it's learning how to read the body language of the opposite sex. How many times have you misunderstood the body language of someone, thinking they were attracted to you and when you made your move you were shot down in flames! The ability to read the body language of the opposite sex can tell you whether they are attracted to you or not from across a room. It can also help keep you from sending the wrong signals yourself. Reading body language is not all that difficult to learn and once you get used to it you will find it is almost instinctive.
One very easy way to tell if someone may have an interest in you is how close they stand to you. If they are standing farther away and move closer this can be an indication that they are interested, on the other hand if they are close to you and move away it can mean the opposite. It's similar to the two foot rule in sales, if they come within two feet of you they are very likely to be interested in you. The reason this is such a big deal is because they are sharing space with you within reach of you and trusting that they are safe with you. If someone stays more than two feet away from you it is almost certain that they are not romantically interested in you.
Mirroring your body language is another way that someone can show that they are interested in you. This is usually done without even thinking about it, but if you notice someone doing it now that you have a little knowledge about body language you can feel comfortable that they are interested in you. In most cases the other person does not even realize that they are doing it, but it is simply instinctive for us to imitate people we want to be close to.
The way that someone stands when they are speaking to you can show body language that tells you whether or not they are interested as well. If someone is speaking to you and they are turned towards you and possible even leaning in towards you it is an indicator that they are interested in you. Much of romantic body language is built around trust and safety. If you appear unguarded then it makes the other person feel safe, if you open yourself up to another person and they mirror that body language, they are most likely interested in you.
One of the largest indicators of romantic interest is eye contact. When we have an interest in someone or we are attracted to them we strive to make eye contact with them and if they maintain eye contact with you they are definitely interested in you. When someone purposely looks away or avoids making eye contact with you they are not interested so either way way you get a pretty clear message from the eyes.
Even though body language is usually understated and involuntary it can also give a clear sign of romantic interest. It seems that because body language is instinctive also makes a very precise signal of romantic interest.