First of all, try to approach this situation in a mature manner. It isn't going to happen overnight so forget simple begging and pleading. Have a conversation with your parents to discover what their concerns are and then determine how you can address those concerns. For example they may be concerned about the cost of feeding and caring for a dog. People here can be a wealth of information on just how much that can actually be. Call a local vet to see what they would predict for general health care per year, etc. Once you figure out a ball park figure, you can indicate how much you can contribute from your birthday money or money you can earn babysitting or whatever. They may have different concerns, for example the shedding factor - you could help by volunteering to do the vaccuuming, etc. ...but the object is to learn what the issues are and then slowly convince them that these concerns really won't be a problem. It's going to take time, but if you go slow and over time show them how much this means to you, and how willing you are to make it work out, you may make some headway.