Sealers are used to enhance concrete durability through their ability to prevent moisture penetration and chloride intrusion, and, consequently, improve the freeze–thaw performance of the concrete and prevent corrosion of the steel reinforcement, respectively. This paper summarizes the results of three years of comprehensive field and laboratory investigations, undertaken at The University of Manitoba, to study the effectiveness of boiled linseed oil and mineral spirits in comparison to a silane and a siloxane sealer. The field investigation examined the performance of the sealers applied to the concrete pavements of a city street, a provincial highway, and an airport apron in Winnipeg, Manitoba. The laboratory investigation included sealer penetration, salt-water absorption and vapour transmission, abrasion, chloride ion intrusion, surface scaling resistance, and rapid freeze–thaw cycling. Test results of the field and laboratory investigation indicated that boiled linseed oil and mineral spirits was the most effective sealer at reducing chloride ion intrusion. It was found that boiled linseed oil and mineral spirits was comparable to siloxane and much more effective than the silane at reducing salt-water absorption. The results also indicated that boiled linseed oil and mineral spirits was most effective at reducing surface scaling and remained effective when subjected to salt-water absorption after abrasion. Key words: concrete sealers, linseed oil, silane, siloxane, absorption, scaling, chloride intrusion.