The process and network structure are forms of horizontal structures, this article explains the two models and their key differences.
Basics of Organizational Development
Discusses the differences, strengths and weakness of two hierarchical structures of an organization.
Explains the Matrix structure which has both divisional and product structures and is more horizontal than either of them.
Discusses the facts and failures of performance appraisals process, the reason why it's mandated and why it remains an ineffective approach in modern organizations.