Strengthening the foundations of the historical Tartu University main building took place in 1995 and was completed in 1996. The work was the second state of the whole strengthening project and covered the central part of the building. The northern part of the building had been strengthened earlier by the end of 1977. The strengthening work was carried out by method of underpinning, using jacked piles. Steel tube piles were jacked down under the structure, using the structure itself as counterweight. Reinforced concrete beams were constructed on both sides of the thick external wall of the main entrance. The concrete beams were pressed with posttensioned anchorage against the structure before piling. Inside the building massive pillars were supported by steel beams and jacked piles. A field load test was performed on each pile and the rate of settlements was measured. Archeological diggings were carried out side by side during the strengt hening work.