Drinking culture varies wildly as you roam from country to country. A party mood rules in Thailand, where 'big bottles' of Singha and Chang beer fuel long evenings of conversation. In Malaysia, conversely, nightlife is low-key and restrained, and Muslim residents are banned from drinking alcohol by law. In general though, there are few places where you can't find a cold beer at the end of a long day.
Each country has its own laws on nightlife and drinking, and away from resorts and big cities, drinking normally takes places at restaurants over meals – or in the case of the Philippines, over karaoke.
Despite its party reputation, Thailand restricts the sale of alcohol between 2pm and 5pm and from midnight to 11am, and additional bans are put in place on Buddhist holidays such as Visakha Bucha. The Philippines is perhaps the most liberal country in the region when it comes to the consumption of alcohol, but drinking in the street is still discouraged.
In Malaysia and Indonesia, Muslim residents are banned from buying alcohol, but alcoholic drinks are still widely available for non-Muslim residents and visitors, particularly in tourist hang-outs. In Brunei, the sale of alcohol is banned completely, but visitors can import a small amount of alcohol for personal use in private. Most countries in the region impose high taxes on alcohol, so prices may not differ too much from what is charged in Western countries.
The official drinking age ranges from 18 to 20, but this is laxly enforced and it is rare to be asked for proof of age, except when trying to enter dance-bars and nightclubs. As well as the legal sale of alcohol, many countries have a busy black market in home-brews and moonshine; a little caution is advised, as toxic batches are not unheard of.