Children develop at their own pace. While most children are speaking by age 3, your son does not necessarily have a problematic delay. Although there may be no cause for concern, you should definitely speak with your pediatrician and ask for a referral for an assessment. Your local school system may also be able to provide a referral and information about available services if your child is, in fact, diagnosed with a speech delay or other physical or learning disability. There are many reasons a child may not be speaking, including physical difficulties with hearing, learning delays, selective mutism, or temperament and personality. In the meantime, consider whether or not your child can follow spoken directions and attempts to communicate with gestures or vocally and if the rest of his development has been on track. Only a specialist who meets with your child in person, however, can assess his speech and diagnose any issues.