“(1) Post-termination restraints are enforceable, if reasonable, but covenants in employment contracts are viewed more jealously than in other more commercial contracts, such as those between a seller and a buyer. (2) It is for the employer to show that a restraint is reasonable in the interests of the parties and in particular that it is designed for the protection of some proprietary interest of the employer for which the restraint is reasonably necessary. (3) Customer lists and other such information about customers fall within such proprietary interests. (4) Non-solicitation clauses are therefore more favourably looked upon than non-competition clauses, for an employer is not entitled to protect himself against mere competition on the part of a former employee. (5) The question of reasonableness has to be asked as of the outset of the contract, looking forwards, as a matter of the covenant's meaning, and not in the light of matters that have subsequently taken place (save to the extent that those throw any general light on what might have been fairly contemplated on a reasonable view of the clause's meaning). (6) In that context, the validity of a clause is not to be tested by hypothetical matters which could fall within the clause's meaning as a matter of language, if such matters would be improbable or fall outside the parties' contemplation. (7) Because of the difficulties of testing in the case of each customer, past or current, whether such a customer is likely to do business with the employer in the future, a clause which is reasonable in terms of space or time will be likely to be enforced. Moreover, it has been said that it is the customer whose future custom is uncertain that is 'the very class of case against which the covenant is designed to give protection . . . the Plaintiff does not need protection against customers who are faithful to him' (John Michael Design plc v Cooke[1987] 2 All ER 332 , 334). (8) On the whole, cases in this area turn so much on their own facts that the citation of precedent is not of assistance.”