We investigate the polynomial-time approximability of the multistage version of Min-Sum Set Cover (Mult-MSSC), a natural and intriguing generalization of the classical List Update problem. In Mult-MSSC, we maintain a sequence of permutations (π 0 , π 1 , . . . , π T ) on n elements, based on a sequence of requests R = (R 1 , . . . , R T ). We aim to minimize the total cost of updating π t−1 to π t , quantified by the Kendall tau distance d KT (π t−1 , π t ), plus the total cost of covering each request R t with the current permutation π t , quantified by the position of the first element of R t in π t .Using a reduction from Set Cover, we show that Mult-MSSC does not admit an O(1)-approximation, unless P = NP, and that any o(log n) (resp. o(r)) approximation to Mult-MSSC implies a sublogarithmic (resp. o(r)) approximation to Set Cover (resp. where each element appears at most r times). Our main technical contribution is to show that Mult-MSSC can be approximated in polynomial-time within a factor of O(log 2 n) in general instances, by randomized rounding, and within a factor of O(r 2 ), if all requests have cardinality at most r, by deterministic rounding.