The hydration characteristics and strength development of a high alumina cement (HAC)/zeolite blended cement in combination with an inorganic salt or alkali, selected from a suite of compounds including sodium sulfate, sodium carbonate, sodium nitrate, sodium chloride, sodium bromide, sodium metaphosphate, sodium metasilicate, sodium hydroxide, potassium hydroxide, potassium carbonate, lithium chloride, copper sulfate, and aluminum sulfate, were studied. HAC/zeolite mortars containing a sodium salt experienced no strength reduction after being water-cured at 38 o C for 150 days. Stratlingite formation is apparently promoted and hydrogarnet formation is significantly inhibited by the addition of sodium salts.