While stock markets provide investors with significant returns over the long run, rare but unanticipated disasters cause severe short$-$term losses. One common practice used to manage risk is portfolio diversification. The literature employs the magnitude and sign of the cross$-$asset correlation to classify assets into three levels: $(1)$ diversifiers, $(2)$ hedges, and $(3)$ safe havens. First, review the literature to define each asset. Next, propose four safe$-$haven assets against stock risk and explain why their correlation to stock markets is negative.