The short answer is – VERY important. The fact is, the better your technical and infrastructure defenses are, the more likely it is that a social engineering attempt will be made on your people.
In 2013, over 89% of breaches and data loss incidents were deemed preventable through security awareness and execution programs. More relevant, 60% were the direct result of social engineering and other attacks that began with employees that had no substantial access to data. Put another way, 60% of the over one billion records lost in 2013 were the result of employees.