This manual is intended to assist office building owners' personnel responsible for funding and operating existing office buildings across the United States. This publication and its companion documents are the products of a Federal Emergency Management Agency (FEMA) project to develop the concept of incremental seismic rehabilitation-that is, building modifications that reduce seismic risk by improving seismic performance and that are implemented over an extended period, often in conjunction with other repair, maintenance, or capital improvement activities. The manual was developed after the project team analyzed the management practices of office building owners of varying sizes located in various seismic zones in different parts of the United States. It focuses on the identified concerns and decision making practices of owners and managers of Class A, B, or C buildings, be they REITs, pension funds, partnerships, individuals, or other types of owners. Earthquakes are a serious threat to office safety and pose a significant potential liability to office building owners. Office buildings in 39 states are vulnerable to earthquake damage. Unsafe existing buildings expose office building owners and tenants to the following risks: Death and injury of tenants, occupants, and visitors; Damage to or collapse of buildings; Damage to and loss of furnishings, equipment, and other building contents; Disruption of office functions and building operations. The greatest earthquake risk is associated with existing office buildings that were designed and constructed before the use of modern building codes. For many parts of the United States, this includes buildings built as recently as the early 1990s. Although vulnerable office buildings need to be replaced with safe, new construction or rehabilitated to correct deficiencies, for many building owners new construction is limited, at times severely, by budgetary constraints, and seismic rehabilitation is expensive and disruptive. However, incremental seismic rehabilitation, an innovative approach that phases in a series of discrete rehabilitation actions over a period of several years, is an effective, affordable, and non-disruptive strategy for responsible mitigation action. It can be integrated efficiently into ongoing facility maintenance and capital improvement operations to minimize cost and disruption. The strategy of incremental seismic rehabilitation makes it possible to get started now on improving earthquake safety in your office building inventory. This manual provides owners of office buildings, be they Real Estate Investment Trusts (REITs), pension funds, partnerships, individuals, or other forms of ownership, with the information necessary to assess the seismic vulnerability of their buildings and to implement a program of incremental seismic rehabilitation for those buildings.