In this paper, we introduce weakly compact version of the weakly countably
determined (WCD) property, the strong WCD (SWCD) property. A Banach space X is said to
be SWCD if there s a sequence (An) of weak ∗ compact subsets of X∗∗ such that if K⊂X is
weakly compact, there is an (nm)⊂N such that K⊂⋂m=1∞Anm⊂X. In this case, (An) is called a
strongly determining sequence for X. We show that SWCG⇒SWCD and that the converse does
not hold in general. In fact, X is a separable SWCD space if and only if (X, weak) is an ℵ0-space.
Using c0 for an example, we show how weakly compact structure theorems may be used to
construct strongly determining sequences.