Each month the World Fellowship of Buddhists has a dhamma talk and meditation in English from 2-5 pm on the first Sunday of every month. Speakers vary month to month. Note that if that day falls on, or close to a holiday, then the event is likely to be cancelled.
In the same building, on the second Sunday of the month is a Forum with the World Buddhist University, on the third floor. They invite a speaker and give a topic. This event goes from 12:30-2pm.
3rd floor, WFB Headquarters Bldg., in Benjasiri Park, Sukhumvit 24, Bangkok. All are welcome to join the programme free of charge. For more information, please [try] call 02-258-0369 to -0373, fax 02-258-0372, or see http://www.worldbuddhistuniversity.com