It is well-known that the growth of a slit in the upper half-plane can be
encoded via the chordal Loewner equation, which is a differential equation for schlicht
functions with a certain normalisation. We prove that a multiple slit Loewner equation
can be used to encode the growth of the union  of multiple slits in the upper half-plane
if the slits have pairwise disjoint closures. Under certain assumptions on the geometry
of , our approach allows us to derive a Loewner equation for infinitely many slits as
well.