Sex is a natural part of life.  Although I remained a virgin until I was nearly 34 years old, I do not recommend it. However, beginning a sexual relationship too young can have a negative impact as well.  I believe that most people should not start having sex until seventeen or eighteen. Then, again, some shouldn't until much later.

It's a matter of maturity and responsibility.  One must be able to put sex into perspective.  Sex can be a progression or another dimension in a love relationship.  Or, sex can be a fulfillment of lust.

The key is honesty.  When two consenting "adults" agree on the objective(s) of sex, it can be wonderful.  In most cases, however, couples often have hidden agendas.  One the partners may say one thing but secretly wants another.  Sometimes, this works.  Most often it leaves the dishonest partner empty and disgruntled.

In my experience, I have found that the failure is not with communication, per se.  More often, it's semantics.  The word "relationship" is the culprit here.  One must define the word and set parameters.  Will this relationship be love, lust, or friendship or even some combination of the three.  Later, it's okay to re-define the relationship or the parameters if both parties agree.

To sum up sex.  Be honest.  Set the ground rules.  Be honest.