Executive Management will have a buy-in on Architecture Security when they have a full understanding of the Security, Reusability, and Cost Benefit.  Security will enable the 'enterprise's to allow staff and customer's the confidentiality, integrity, and accessibility they desire.  Reusability will allow the enterprise the ability to forcast financial initiatives overtime to the primary goals and needs of the company.  Cost Benefit allows the enterprise to invest in a security system as a preventive tool now, verses a reactive tool in the future.  Building a relationship on trust and protecting creditability.

The best way to sell your architecture program to executive management is to show them a clear return on investment. Since the majority of executive management may not understand or care to understand the technical aspect of what you are doing, their concern will be primarily focused on what kind of return the company will get.

We have already learned that management can get stingy when talking about the expense a security program will cost. The best way to sell your management is to break everything down into their terms and explain the return on investment that they could receive. Showing the benefits and the saving the company can receive will go a long way into talking management into buying.

I agree with Brian that executive management to know about the Return on Investment. All they care about is dollar & cents. Another way to sell your architecture plan is to present a diagram of the plan. If you present a diagram of the plan & break it down to a language that they'll understand as well as show them how they it will help them get a return on investment, you should be able to sell your plan effectively.

The architect will have to communicate the vision and be able to translate the business strategy into a technical strategyin which upper management can relate to.  The architect's solutions must create value for the business.  They have to translate and innovate what competitive edge the organization will receive from the plan. Most important, the architect will need to break the complex system down into an understandable plan/language where upper management can see the benefits of the architectural program.

Besides being able to communicate clearly and effectively, a great deal of managements focus will be on the return on investment. Someone also mentioned reusability....that's a biggie. No need to re-invent the wheel if the code, security mechanism etc is already available. Upper management will definitely want to have the check mark in the box exclaiming security mechanism are in place.

I agree, you have to break things down into terms that management can understand.  You have to show them how much money you will save in the long run and you have to show them how much money you stand to lose if there is no action.  Anything that displays some sort of lost revenue to the company will harden your justification for implementing an architecture program.