>The system I am writing needs to validate people applying for an account as being 18 years old or older. Anyone under 18 should not be allowed an account. It sounds simple, but one of my versions that included detection of leap years got very complicated, hence my question here.
>
>Simon


Simon, try this & see if it works for You (the function is not very well tested):

? CalcAge(DATE(1965, 4, 26), DATE(2004,4,27))

FUNCTION CalcAge(b_day, to_date)
  LOCAL fmnts, smnts
  fmnts = YEAR(b_day)  *12+MONTH(b_day)

  IF MONTH(to_date) == MONTH(b_day) .AND.; && If The day is smaller then day of birthday the person has not complete full year
     DAY(to_date)   <  DAY(b_day)
     smnts = YEAR(to_date)*12+(MONTH(to_date)-1)
  ELSE
     smnts = YEAR(to_date)*12+MONTH(to_date)
  ENDIF

RETURN INT((smnts-fmnts)/12)