Set-off of losses across heads restricts business loss against salary and limits set-off of house property loss against other income. Set-off permits an assessee to adjust a net loss under any head (other than Capital gains) against income under other heads in the same assessment year; where the loss arises and the assessee has capital gains it may be set off against any head including Capital gains. Loss under Profits and gains of business or profession cannot be set off against Salaries, and Capital gains loss cannot be set off against other heads. House property loss is limited for set-off to the extent it exceeds the prescribed threshold.