Preface

Business planning is often conducted when:
Starting a new venture (organization, product or service)
Expanding a current organization, product or service
Buying a current organization, product or service
Working to improve the management of a current organization, product or service
There are a wide variety of formats for a business plan. The particular format and amount of content included in a plan depends on the complexity of the organization, product or service and on the demands of those who will use the business plan to make a decision, eg, an investor, funder, management, Board of Directors, etc.
Overall, the contents of a business plan typically aim to:
Describe the venture (new or current organization, product or service), often including its primary features, advantages and benefits
What the organization wants to do with it (buy it, expand it, etc.)
Justification that the plans are credible (eg, results of research that indicate the need for what the organization wants to do)
Marketing plans, including research results about how the venture will be marketed (eg, who the customers will be, any specific groups (or targets) of customers, why they need the venture (benefits they seek from the venture), how they will use the venture, what they will be willing to pay, how the venture will be advertised and promoted, etc.)
Staffing plans, including what expertise will be needed to build (sometimes included in business plans) and provide the venture on an ongoing basis
Management plans, including how the expertise will be organized, coordinated and led
Financial plans, including costs to build the venture (sometimes included in business plans), costs to operate the venture, expected revenue, budgets for each of the first several years into the future, when the venture might break-even (begin making more money overall than it has cost), etc.
Appendices (there are a wide variety of materials included in appendices, eg, description of the overall organization, its other products and/or services, its current staff, etc.)
Nonprofit readers might notice that a business plan is very similar to a well designed grant proposal. In addition to the above items, a grant proposal might include itemization of any deficits (when expected expenses exceed expected revenues), which indicates the need for funding from the particular funder to which the grant proposal is being submitted. Also, a break-even analysis usually isn't included in a grant proposal.
Quite often, an organization's business planners already know much of what will go into a business plan (this is true for strategic planning, too). However, development of the business plan greatly helps to clarify the organization's plans and ensure that key leaders are all "on the same script". Far more important than the plan document, is the planning process itself.