1. US20150117418 - Communication efficiency

There is provided a method, comprising: detecting, by a node of a first wireless network, that at least one overlapping second wireless network is configured to apply contention periods and contention-free periods for communicating with different subsets of devices; detecting that a contention period timing applied by the at least one overlapping second wireless network is not aligned with a contention period timing applied by the node of the first wireless network; and causing a modification of the contention period timing in at least one of the wireless networks in order to have the contention periods to take place at least partly at the same time in each overlapping wireless network.