Fluxes and exchange coefficients are derived for the transport of 90Sr, 210Pb, 210Bi, and 210Po between the free troposphere and the marine boundary layer and between the boundary layer and the sea surface. Radionucleide concentrations previously measured near Hawaii are used in the derivations. Values obtained for the free troposphere/boundary layer exchange coefficient (expressed as a piston velocity) were 185, 228, and 203 m d-1 for 210Pb, 210Bi, and 90Sr, respectively. The magnitude of the total sea-surface source of 210Po is also determined.