If you want to know which tech skills are in demand, take a look at the market value of tech certifications. Employers are often willing to pay a cash premium above base salary for tech pros with certifications in vital technology areas such as security, explained David Foote, chief analyst of Foote Partners LLC. They’re also willing to pay big for tech pros who are certified in emerging technologies, at least until the supply of talent catches up with demand. (Many employers have even shown a willingness to pay for employees’ certification classes.) But which certifications are seeing the biggest increases in pay premiums and market value? Here’s a look at the ones that registered the biggest gains during the first half of the year, based on data collected for Foote Partners’ IT Skills and Certification Pay Index. If you’re currently recruiting talent, you may end up having to offer some strong salary numbers to pull tech pros with these certifications into your company.