Abstract The rate of insect population growth in stored seed is strongly influenced by both the seed temperature and moisture content so both need to be taken into account when using aeration to control insect populations. This paper explains how to do this by using Seed Wet-Bulb Temperature (SWBT). Strategies for, and benefits of, using SWBT to manage aeration systems are explained, including: the use of SWBT to predict the rate of insect population growth, how to select a target SWBT for controlling insect populations, and how to select an aeration controller setting that will achieve the target SWBT. It is shown that SWBT control of aeration systems has particular benefit in warm temperate climates and the implications for moisture migration are analyzed. Essential data needed for using SWBT to manage aeration systems are provided including figures that give SWBT data and limiting conditions for mould growth, for nine types of seed. The methods used for determining SWBT and for determining the conditions that promote growth of moulds are detailed.