Abstract. The Multi-points Expected Improvement criterion (or q-EI) has recently been studied in batch-sequential Bayesian Optimization. This paper deals with a new way of computing q-EI, without using Monte-Carlo simulations, through a closed-form formula. The latter allows a very fast computation of q-EI for reasonably low values of q (typically, less than 10). New parallel kriging-based optimization strategies, tested on different toy examples, show promising results.