It is advisable not to pay salary to your wife for recruitment services. you can pay salary to your wife and claim it as expense only if she is qualified for the job she is employed for, As your wife is an Engineer by qualification , she should be rendering service to your organisation thats requires the skill and competence of an engineer and you should be able to prove that she is working like a regular employee (i.e around 8 hours for 24 or 25 days in a month), if you fail to prove 1 or more of any of these said points her income will be clubbed with yours. as recuritment(most of the time) doesnot need qualification of an engineer, there is a risk that the expense might get disallowed