Parenting is the ultimate long-term investment. Be prepared to put far more into it than you get out of it, at least for some time. Given the stresses of contemporary American culture, the happiness of couples plummets the minute they become parents. And it gets worse before it gets better. In the long run, it is the most rewarding job of your life.
From talking and reading to infants to making values clear, parents exert enormous influence over their children's development. They are, however, not the only influences, especially after children enter school. It's especially important that parents give children a good start, but it's also important for parents to recognize that kids come into the world with their own temperaments, and it is the parents' job to provide an interface with the world that eventually prepares a child for complete independence. In a rapidly changing world parenting seems subject to fads and changing styles, but the needs of child development as delineated by science remain relatively stable.