Silo smashing can occur for clients (I've actually been in rooms where in-house sales, marketing and communication teams rarely, if ever meet except to discuss budget issues). It can also occur within a communications organization. If the only time teams meet is to discuss a specific project/initiative (i.e. new trade show booth) and not examine a holistic approach to marketing communications, they may miss an opportunity or new perspective to more effectively target and reach potential stakeholders.
Effective silo smashing is about facilitating relationships across organizational and departmental lines, encouraging internal collaboration, and fostering opportunities to effectively raise awareness of a product/service/idea and foster an organization's brand awareness. Being able to "walk through walls" to meet with and get other organizational leadership and knowledge experts to collaborate often yields better overall ROI for marketing and communication plans.
Professional communicators are in the best position to be the silo smashers in that communication and marketing development means taking a "big picture" approach to solving a client's business issue. Consequently, the expertise and information that is needed to build, implement, measure and sustain a successful communications campaign means reaching out past those whose responsibilities are confined to marketing and communications . Often professional communicators are welcomed (even if it is with a healthy dose of skepticism) when they reach out to other departments for information.
Communication plans that take place in a vacuum are less effective than those that are developed with input from relevant parties that have a different perspective on certain aspects of a product/service/program. Depending on the organization and the goals of the campaign, communicators may need to and should reach out to individuals in research and development, finance, design, and other subject matter experts to effectively communicate the value and develop a robust and effective marketing communications campaign to achieve an organization's goals. Having more information to understand the business case as well as the technical and creative case will only help to make the campaign more robust and unique. It will also help to expand the support and enthusiasm for marketing and communication efforts throughout the organization.
People often want to give their opinion and demonstrate their expertise when it comes to promoting and educating stakeholders about a product/service/idea. Learning how to smash internal client silos is a good step in enhancing client service while raising trust and creating a lasting partnership for many years to come.