A configuration of aspects formed when two points of a horoscope are in opposition to each other and in quadrature to a third planet.

F.Sakoian and L.Acker find in the T-square the character of Saturn, and consider that this configuration gives certain obstacles and the necessity of overcoming them, and also a strong, vigorous, ambitious aspiration to act, indicative of its Saturnian character. Pressure and an appreciation of conflict are necessary here for resolving a planet in quadrature. When the energy of T-square moves a mature person, it frequently leads to significant achievements. The T-square is a push to success, and many well-known people have it in their natal charts. In interpretation it is necessary to take into account the cross of qualities in which the T-square occurs. Sakoian and Acker remark that the T-square indicates immediate crisis situations, and this quality is strongly accented in cardinal signs or angular houses.

M.March and J.McEvers state that in a T-square the opposition is connected with attitudes and the square with actions; as a whole, it is a dynamic configuration from which the native derives driving strength. If the T-square is in cardinal signs the person is dynamic, quick and starts to act instantly, even if the situation is extremely dangerous, and is inclined to interfere with other people's affairs. When the T-square is in fixed signs the native operates slowly, but is resolute; as a preliminary, he will always find out all the possible problems before starting to act. A mutable T-square usually indicates a person opposed to people and ideas; obstacles here can be indecision and wavering.

In M.Kozyritskoj and M.Levina's view the T-square is perceived by associates of the native as forceful, clumsy aggressiveness. This configuration occupies a semicircle of the horoscope, and the native feels an emptiness in other hemisphere, and intuitively tries "to fill the void" in order to counterbalance the figure. There is a problem of self-assurance. According to some astrologists great attention should be given in the analysis to the zone diametrically opposing the planet with the two square aspects. Subconscious promptings are focused into this area as the native's discontent with destiny grows. In daily life it is necessary to monitor closely transits through this area - during these periods there are often fateful life events. If the person is not sidetracked by self-assurance issues, he or she can solve very complicated problems, such is the power of the acquired T-square. In the half of the chart where the strong-willed pressure is required, the energy for uncommon success is possible in those areas, for example, politics.