Tax deduction at source on casual winnings requires flat rate withholding, surcharge and strict TAN, payment and reporting compliance. Deduction of tax at source is required on winnings from lotteries, crossword puzzles and horse races under sections 194B and 194BB, with such casual income taxed under section 115BB at a flat rate of 40%. Winnings below the statutory exemption threshold in aggregate are not taxable; where winnings exceed that threshold tax is deductible on gross winnings after treating the exempt amount and after excluding commissions to agents. Deductors must quote TAN in specified documents, file prescribed returns, deposit TDS to Government within prescribed time, and face civil and criminal consequences for defaults.