The determinants of the number of children in local authority care in England are examined using methods that distinguish the implications of current flows into and out of care from the continuing impact of past decisions. In the long term, the decline in the admission rate and the time that children can expect to spend in care between 1977 and 1986 would produce a 39 per cent fall in the number of children in care from that implied by flows into and out of care in 1977–8. These changes have been compounded by an 11 per cent decline in the size of the child population. In fact, though, the higher level of admissions in the past means that the number in care fell by only 29 per cent during this period. If admissions and rates of leaving care have remained at their 1985–6 levels since then, the number of children in care will drop by around 8,300 to under 59,000 in 1991.