  We have carried out extensive density functional calculations for series of
sodium clusters $Na$$_{N}$ ranging from $N$=10 to 147 and have obtained
$\approx$ 13000 distinct isomers. We unravel a number of striking features of
the growth characteristics. The growth shows order-disorder-order pattern of
cyclic nature. Between two ordered clusters the growth proceeds via disordered
clusters having multi-centered icosahedral local order. The Global order
emerges suddenly with the addition of one or two atoms only. The clusters
around $N$=92, the electronically closed shell system, behave completely
differently and do not show the favored icosahedral local order. It is the
absence of icosahedral local order which is responsible for rather low melting
temperatures observed in the experiments.
