Much debate as to which group deserves most attention. The short answer is that stockholders are the most important, but we often read or hear reports that look different from this claim. Many authors and business leaders cite differing stakeholders as the most important. People are not in an organization, people are the organization. No, because only if employees are happy can they make customers happy which will then make stockholders happy.
Many marketing oriented books and businesses, the customer is deemed to be the most important.
For example at Stew Leonard's grocery stores there are three-ton rocks stating the rules of the company. In part it is because the various groups all want to be the most important. For example, management frequently argue that they make the decisions and thus are the keys to the organization and as such are the most important stakeholders. Probably a more likely explanation is that the argument centers on semantics. Without an emphasis on employees or customers the goals of the shareholders will not be satisfied.