Sir: Indeed Ramzan is Islam’s holiest month; it is a time of reflection for Muslims around the world. It is also a time, symbol and reflection of the unity of Muslims around the world. However, practically what is happening is that the moon sighting procedure to determine the first of the holy month becomes a cause of disunity amongst Muslims each year. Take the example of this year only. Most Islamic centres and mosques of North America announced the first day of Ramzan on June 28 based on astronomical calculations of moon sighting, which are almost 100 percent correct. So-called moon sighting committees of North America, Arab countries and an unofficial body in one province of Pakistan announced the first day on June 29. And so-called moon sighting committees of Pakistan and India announced that the first of Ramzan would fall on June 30. The Muslim clerics responsible for announcing moon sighting never think that due to three different days for the start of Ramzan, they have caused disunity among Muslims around the world. Many Muslim clerics often announce successful interfaith dialogues with Jews and Christians, but they never think about intrafaith dialogues with their own co-religionists to resolve the controversy of moon sighting in order to have unity of Muslims around the world so that they celebrate this holiest month on one and the same day. In this era of technology, when scientific inventions and facilities are used in every sphere, it is high time that astronomical calculations of moon sighting be used worldwide like astronomical calculations of sunrise, sunset, etc., are used by every mosque worldwide to determine prayer timings. Qasim Abbas Toronto, Canada