The top-down approach to security is when an information security program moves ahead with management approval. The appropriate security funding is secured and there is a proper plan and direction towards the program. This approach is more efficient and generates better results. In short, the top-down approach is a more active and serious approach to security.
In contrast, the bottom-up approach to security is a reactive approach to solving information security concerns. Only after there has been a data breach or several hacking incidents does the company decide to act. This approach will only generate “stop gap” results and not long term results.