After choosing a breeder and deciding what type of lab you would like, the next decision is to pick out the sex of the dog. There are some differences, but the overall thing to remember is that one sex does not make a better dog over the other. Most of the difference is purely physical. Males are usually stronger and bigger, but that does not mean they are more aggressive. The only time they are known to be aggressive is when females are in heat, but that is only with other male dogs. Females are in heat many times in their life, and may have hormonal mood changes due to that, but spaying can take care of both. Some people think males wander more or females are more loving with families, while other people think the opposite. It is really a matter of personal preference on deciding whether male or female. Regardless of the sex, they both make excellent companions and can perform the exact same jobs.