A liquid desiccant dehumidifier includes a liquid desiccant absorber arranged to receive concentrated liquid desiccant and absorb moisture contained in ambient air passed through the absorber thereby diluting the liquid desiccant. A first heat exchanger is operative to heat dilute liquid desiccant received from the desiccant absorber prior to passage to a boiler that evaporates moisture from the diluted liquid desiccant to create steam and reconstitute the desiccant into a concentrated liquid desiccant. Dilute liquid desiccant from the first heat exchanger first passes to a condenser that receives steam from the boiler and sensibly heats the dilute liquid desiccant to a higher second temperature without direct exposure to steam or air. A second heat exchanger communicates with the condenser, the boiler and the first heat exchanger and is operative to further heat diluted liquid desiccant received from the condenser to a higher third temperature prior to entry into the boiler by recovering waste heat from the boiler. A pump draws concentrated liquid desiccant from the boiler through the heat exchangers and passes it to the absorber.