Don't worry. It's not an impossible situation. It just requires the designer and the writer to work together on two key steps:
Site architectureBefore the design starts, you should develop the site architecture. The menu will guide much of the design and, obviously, the content. Your writer may lead this part of the planning but, more than likely, a team of people will have input into the site map and structure.
WireframesThe designer will take the lead here. Using your defined site architecture and stated website objectives, the designer will develop a set of wireframes that will give the design and content a framework. The wireframes will account for pages that need to communicate different types of content and give a structure for the content writer to work within. That framework will also provide necessary constraints as the design is developed.
Read more of our thoughts on the importance of site architecture and wireframes.
Once the wireframes are approved and communicated to your team. The heavy lifting starts. Now the design concepts are created while, often at the same time, the content is developed. When the two pieces come together, there will likely be some fine-tuning involved to tweak the content or rewrite calls to action to best fit the design.
With the right planning, design and content come together to create an effective, strategic and functional website.
So which comes first? Neither - it's all about the strategy. Need some help developing your website strategy? You've come to the right place. Let us help you realize (and maximize) the potential of the Internet.