The global economic power shift towards the East has caused the governments of developed economies to support national businesses which are involved in the process of internationalizing and expanding across borders. Commercial diplomacy provides a means for governments to increase their international trade and to stimulate their national economies. Foreign posts play a crucial role in offering effective diplomatic support for international business. But what are the factors that can explain commercial diplomacy effectiveness at the foreign post level? This paper presents the results of a survey that was conducted among commercial diplomats stationed at foreign posts. It appears that the amount of experience that commercial diplomats acquired at these foreign posts, combined with their established business network form two of the most important factors which have a positive impact on the quality of commercial diplomacy. This extends further to include the importance of the client (business) preparedness in terms of knowledge and skills as well. Furthermore, the results indicate that the less favourable a cognitive institutional environment in a host country is, for instance in terms of information availability, then the more relevance commercial diplomacy will have. The results of this study promote the understanding of how commercial diplomacy works and show how the debate on the future of commercial diplomacy can be taken a step further. This study should also be seen as a starting point for an holistic framework of commercial diplomacy effectiveness