In which countries should I aim to obtain patent protection?

A patent is a territorial right, which implies that the right only applies in the country where the patent is granted. It is advisable to file for patent protection in countries with large economies, or countries expected to show growth in your particular field. As patenting in many different countries is expensive, a selection of the most important countries must be made. This will often be sufficient, as development and marketing in the remaining countries will often not be of sufficient interest to the competitor.