I have seen a lot of people who are concerned about penis size and as stated in each response, it is something that most men shouldn't be concerned about. I do understand, however that there are a group of men who are smaller than what could be considered average.
If you look into the ways of penis enlargement it seems that apart from risky surgery, you are stuck with what you were born with. This is not the case. The concern of penis size is not just a recent one. Men have troubled themselves over this for thousands of years and some actually stumbled onto a good thing. The technique I am going to share with you is what my ex-girlfriend's father shared with me during a bit of one-to-one. My ex-girlfriend and family were African (which is where the technique comes from) and for generations they have openly shared between family members and close community a method called jelque.
Jelque is basically a way of excersising the penis. The corpora cavernosa (the spongy tissue inside the penis) works on the same priciple as muscle tissue when exercised. This means that if you break down the tissue, it will grow back thicker and stronger. To perform the technique, you will need a lubricant, baby oil or massage oil will do fine. Lubricate your penis and get your self semi- aroused (So it's swelled, but not erect completely) and then make your thumb and forefinger into an 'ok' sign around the base of your penis. Ensure your grip is tight but NOT tight enough to be painful. Slowly pull your fingers to the end of the shaft of the penis then release. Ensure you do not go over the Glands or head of the penis. Follow with the opposite hand and continue to switch hands consecutively. You can compare the hand movements to milking a cow. As you get used to switching hands gradually increase your speed. If your penis begins to get fully erect, STOP and wait until the erection has began to subside. It can be damaging to perform the technique with a fully erect penis. If you feel the urge to ejaculate at any time, stop and wait until the feeling has subsided, then continue. Do this for 20-30 minutes on a daily basis. You should see a marked improvment in 2 months. You can even ask your partner to do this with you. It can help ease insecurities by sharing the experience and your partner will feel more involved instead of being shut out from problems which can cause tension and can be sexually stimulating for both parties.