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Two constructions of contact manifolds are presented: (i) products of S^1with manifolds admitting a suitable decomposition into two exact symplecticpieces and (ii) fibre connected sums along isotropic circles. Baykur has founda decomposition as required for (i) for all closed, oriented 4-manifolds. As acorollary, we can show that all closed, oriented 5-manifolds that are Cartesianproducts of lower-dimensional manifolds carry a contact structure. Forsymplectic 4-manifolds we exhibit an alternative construction of such adecomposition; this gives us control over the homotopy type of thecorresponding contact structure. In particular, we prove that CP^2 \times S^1admits a contact structure in every homotopy class of almost contactstructures. The existence of contact structures is also established for a largeclass of 5-manifolds with fundamental group Z_2.

Contact structures on product five-manifolds and fibre sums along circles