Sex contracts are a great way to boost your love life, says leading sex therapist Tracey Cox. According to Cox, getting couples to sign a contract specifying a minimum threshold for sex per week (or month) can work wonders for your libido. Particularly for couples in long-term marriages that struggle to keep the passion alive. “Desire naturally falls over time and the routine of real life tends to take over. Sex - nearly always last on the daily 'to do' list - inevitably gets pushed onto the 'do tomorrow instead' list. And again the next day,” says Cox. “Getting couples to sign a 'sex contract' is a remarkably effective way to get things back on track if you're having a few wobbles with your love life. “It's reassuring. Having a plan to solve whatever problems you're struggling with is comforting. Something's being done; there is a solution,” she adds. Cox also has some tips on how to actually formulate a sex contracts. These include honestly discussing what both partners think of their sex life, coming up with a reasonable and simple plan and sticking to it for at least six weeks, as this is how it takes to implement a permanent change, says Cox. “Your contract should go something along the lines of 'I promise to have sex with you once a week and come up with something new to try at least twice a month. In return, you promise to kiss me more, spend more time on foreplay and give me lots of compliments in bed,'” concludes Cox.