Let {Sn = (Xn, Wn)} n≥0 be a random walk with Xn ∈ R and Wn ∈ R m . Let τ = τa = inf{n : Xn > a}. The main results presented are two term asymptotic expansions for the joint distribution of Sτ and τ and the marginal distribution of h(Sτ /a, τ /a) in the limit a → ∞. These results are used to study the distribution of t-statistics in sequential experiments with sample size τ , and to remove bias from confidence intervals based on Anscombe's theorem.