Congenital heart disease is usually regarded as an esoteric field of medicine, dealt with primarily by dedicated specialists. However, over the last two decades, increased attention has been given by the medical profession, the media and the general public to the possible association between a minor and common congenital heart defect, namely patent foramen ovale, and stroke. In recent months, unusual and unfortunate circumstances have made this topic one of the most fiercely debated medical issues in Israel. It is the belief of the authors of this paper that the association of PFO and stroke can be better understood if the PFO is viewed as part of the broader context of congenital heart disease, and as such it will be presented. Paradoxical embolism is a mechanism of stroke unique to congenital heart disease. The direction and volume of shunted blood in various conditions have a central role in determining the risk of stroke, as will be explained. With this basic knowledge in mind, we shall critically assess the potential role of PFO in stroke patients, suggesting that each case be evaluated individually using the above-mentioned principles. Conditions that enhance the formation of clot or other embolic material will be discussed briefly. The review will conclude with the various treatment options and our center's own experience with this challenging topic.