landlord. On the expiration of the first 20 years, the landlord demanded a rent of N250,000 per annum while the tenant offered N12,000. Part of the rent review clause states: “the amount at which the revised rent shall be fixed… shall be such as in the opinion of the Arbitrator is a fair and reasonable rent for the premises having regard to rents obtainable at the commencement of the revision period for similar lands of similar areas and amenities similarly situated.” The landlord demanded rent based on the building on the premises; the tenant offered rent based on the fact that the premises were undeveloped. The tenant succeeded. 2. Equity: as a result of the harsh rule of quicquid, equity formulated the principles variously styled laches, acquiescence/proprietory estoppel to ensure that justice is served. Proprietary Estoppel So very often, lawyers use the expression laches and acquiescence. Laches means delay. Acquiescence means knowledge that a person‟s interest is being infringed and he keeps silence at the time he should scream out. These two expressions (laches and acquiescence) do not quite capture the meaning or principle of proprietary estoppel. Proprietary estoppel means ownership; that the person relying on it has interest in the land or property. The squatter needs not prove that he has been spending money on the land. Any evidence of possession is enough. If an improver succeeds in his plea of proprietory estoppel, he becomes the owner of both the land and the improvements on the land; the title of the original owner extinguishes. Ingredients of Proprietory Estoppel The rule of proprietory estoppel was laid down in Ramsden v. Dyson (1866) LR 1 H.L. 125. The case was the House of Lords decision that first painted its broadbrush. The