Credo: Less Is More

Pressurize the building: Air evacuated through bathroom and kitchen exhausts, elevator shafts, pools and spas should be offset with conditioned, dehumidified air in slightly greater volume. Otherwise, untreated outside air will infiltrate your hotel and potentially cause mold and mildew problems.
Installing a heating, ventilation and air conditioning (HVAC) system that can dehumidify the space to less than 60 percent relative humidity in both full and part-load conditions is the first step. To keep that level of performance be sure the staff properly maintains the equipment including regular filter and coil cleaning.
Install the right size air conditioning equipment. Oversized air conditioners, especially those without humidity controls, can contribute to moisture problems because the space will reach the desired temperature before sufficiently lowering the humidity.
Manage moisture from indoor pool & spa areas with proper ventilation and pressurization, application-specific dehumidification units and effective isolation of the pool area from other parts of the hotel.
Housekeeping and maintenance personnel should be mindful other sources of moisture in the hotel such as wet cleaning and have procedures to dry / dehumidify the spaces to prevent moisture damage. Avoid completely shutting-down HVAC in unoccupied areas as the lack of dehumidification and ventilation can create ideal environment for mold and mildew growth.