• CREDIT HONESTY. 'When a child does something wrong and admits to it, praise their honesty rather than simply punishing the transgression,' advises Dr Victoria Talwar, developmental psychology professor at McGill University, Montreal. 'Children can then understand that although there are consequences for the transgression, there's consideration for the fact they're being honest.'
• ADDRESS THE BEHAVIOUR THAT THE LIE IS COVERING UP. For example, if your child steals a toy from another child and then lies about it, deal with the stealing first and the lie second.
• DON'T SET TRAPS. Sometimes we put children in the position to lie by asking them if they know they have done something wrong. This is self-defeating – they are going to be more tempted to lie to try to get out of the situation.
• MAKE AN EXTERNAL APPEAL. Something like 'Mummy will be very proud of you if you tell the truth' works well for young children while internal appeals work better for older children, such as 'You'll feel great about yourself if you don't tell lies'

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