Maintenance of accounts required for specified professions and businesses to enable computation of taxable income under statutory thresholds. Section 44AA requires specified professionals and other persons meeting statutory income or turnover thresholds, or falling under certain deeming or presumptive provisions, to keep and maintain books of account and other documents sufficient to enable the Assessing Officer to compute total income. The Board may, by rules, prescribe the nature, form, particulars, place, manner and retention period of such records, and higher thresholds apply to individuals and Hindu undivided families.