'Knowing your enemy' in a business context translates into understanding your competition. This can be achieved through thorough market research, including analysis of competitors' products or services, pricing, marketing strategies, customer base, strengths, and weaknesses. Tools such as SWOT analysis and Porter's Five Forces can be particularly useful. Additionally, staying updated on industry trends and developments can provide insights into potential competitive threats and opportunities. Remember, knowing your competitors isn't about copying them but rather about identifying gaps that your business can fill and differentiating your offerings effectively.