If you know that the company is going through a bad patch financially, then you are probably better off waiting until things are a bit easier, so that you have a greater chance of your plea being heard sympathetically.
One useful thing to do is to use the internet to try and find out what the average salary is for your particular job and go in armed with a few facts and figures. One job site, www.reed.co.uk, has a salary calculator which may help you to determine whether you are earning more or less than the average for your job.
These calculators will have their limitations though, as they cannot account for individual circumstances and companies, so simply use anything like this as a guide.
Some salaries will not be negotiable, such as certain civil service jobs, for example, so be sure you are entitled to negotiate before you try to. It will save embarrassment.
