A landlord who terminates a lease for breach and retakes possession cannot measure loss of bargain damages by reference to its own trading profits or losses from conducting a business on the premises. The ordinary measure remains the difference between the lease rent and the market rental value. The landlord bears the onus of proving loss by adducing evidence of market rental value or of unsuccessful attempts to re-let; without such evidence, no prima facie loss is established and no question of mitigation arises. The word 'profits' in the classic formulations refers to income from exploitation of the land (including rent from re-letting), not business profits. There may be limited exceptions where business continuity is necessary to preserve a licence, but this requires evidence of inability to re-let.
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