In conjunction with the Manual on the WMO Information System (Manual on WIS) (WMO-No. 1060), the Guide to the WMO Information System (Guide to WIS) is designed to ensure adequate uniformity and standardization in the data, information and communication practices, procedures and specifications employed among WMO Members in the operation of the WMO Information System (WIS) as it supports the mission of WMO. The Manual on WIS, Annex VII to the WMO Technical Regulations (WMO-No. 49), contains standard and recommended practices, procedures and specifications. The Guide to WIS contains additional information concerning practices, procedures and specifications which Members are invited to follow or implement in establishing and conducting their arrangements in compliance with the WMO Technical Regulations and in developing meteorological and hydrological services.