Many reasons including:
Solve a pressing problem quickly
Gain outside review of operations/process Supplement internal team
Catalyst for change
Management support
Impartial employee review
{Strategic, Tactical} planning Confidential tasks
Isolate company identity
Many more
Regardless, reason(s) should drive process How do you measure success?
How do you manage consultants?
How can you not get your money's worth?
How much should you spend?
Why reviews
Solve a pressing problem quickly
No internal sense of urgency or available resources
Set clear time frame

In some cases, someone else (your board, your investors, or your management team) may have forcefully suggested that you bring in a consultant. or you may believe you can use outside assistance Working with a consultant is something like taking a commercial tour package. Before you even know where you want to go, you should begin to think about why you want to take the trip. You can't begin to address issues such as: How do you manage consultants? How can you not get your money's worth? How much should you spend? unless you understand why you are using a consultant and the implications of your motivations.

The following section discusses some common reasons for using a consultant.

Solve a pressing problem quickly Hopefully, you and your company strive under a sense of urgency. Even so, there are times that you must solve a pressing problem quickly and yet you lack resources. In some cases, your folks are working as hard as they can and any reallocation will do more harm than good. In other cases, you have little or no confidence in your internal teams ability to provide a timely solution. By using a consultant and setting a clear time frame, you can solve a problem in a fraction of the time it would otherwise take. You may have to give up some things to get a consultant to complete the task quickly. It may cost more. Some of your own employees may be bent out of shape. But if the problem is critical and time is of the essence, many consultants can help you turn the corner with some sticky problems. There are consultant who thrive under short time deadlines. These folks often prefer a closed ended project that brings you results and them satisfaction.
Example: You may want to bring in a new sales tracking system. Your own internal support organization is up to its eyeballs in keeping your development system operational. Your own sales team is fighting to make quota. An experienced consultant can help you select a system and even implement it

Gain outside review of operations/process
We've all been there. We are so involved in day to day operations that we can not see the trees from the forest. We're so busy fighting fires that we do not have the attention span, the time, the interest, or the impartiality to review key operations and processes. Often our own view is so clouded either by our buying our own propaganda or by our frustration, that we can't take a fresh look at things.
Example: Your sales and marketing departments seem to be at a constant state of warfare. You have had numerous staff meetings trying to deal with this. An outside consultant can look at the personnel, objectives, and processes and tell you how good or bad it really is and, hopefully, facilitate improvement.

Supplement internal team
Most organizations require periodic assistance in helping an internal team achieve its goals. Your own staff may lack time to complete some tasks. You may not have anyone with the appropriate skills and you probably could value from the experience of others.
Example: Your company has an ongoing customer support organization but this group is struggling to measure customer satisfaction. An experienced consultant can help them create an ongoing program that they can ultimately manage to implement while providing the support organization with ownership of the process.

Catalyst for change
We all error on the side of taking too long to implement necessary changes. You may have non-performing personnel or you may wish to become more "marketing" oriented. The external consultant can bring in credibility. We all pay to hear experts. That expert can be the launch vehicle to implement change while building internal consensus. Change is difficult. An outsider can make it easier on all the parties.
Example: You have a development manager who does not believe in project management. Yet nothing seems to be happening on time. An outside consultant can either persuade your development manager to create an ongoing project system or support a change in personnel.

Management support
Being a CEO in a company is usually a fairly lonely job. Your staff may be working hard but it can be difficult to muster sufficient support for your positions. Often there is a "them vs. us" attitude. You need a reality check and you need one more voice to support your plans.
Example: You may want to implement a new compensation program. Your own folks view compensation as a given right but really have no idea how it can be improved. If you make changes, they may view it suspiciously. Using a consultant can help support your program as well as give you a valuable sounding board that does not exist within your own company.

Impartial employee review
Very few companies have the good fortune not to have non-performing employees. Your intuition may tell you that a key player simply is not up to the job. A consultant can review the employees and let you know how good (or bad) they really are. There is always room for improvement and if the consultant believes that the non-performer can be saved, he or she can come up with a plan for improvement. Along the way, you can document the process and minimize the implications of law suits associated with termination
Example: You have a CFO who seems to be able to produce financial reports but does not seem to be able to work with your bankers or provide good cash flow analysis. You can bring in a consultant to work with that person and determine either processes for improvement or tell you why that person is not going to make it.

Strategic, Tactical planning
All companies have some sort of plan. It may reside in the head of the CEO. It may even be documented. Yet the reality is that planning takes time and effort. A CEO can bias the process thus diminishing the universal ownership of the plan or even miss elements that are necessary. A good consultant can facilitate the planning and then assist in establishing methods for two-way communications and measurement. Keep in mind that a plan is only good if it is implemented and adjusted.
Example: You may want to grow your company through new products or new personnel. Yet all of these issues tie into the ongoing operations. A good planning consultant can "teach" your team how to plan, facilitate the dialog and document the outcome and then suggest proven methods for success.

Confidential tasks
While open communications is important, the consequences of certain potential tasks may require that you maintain strict confidentiality. With an outside consultant you can isolate the task and process and enforce confidentiality.
Example: You may want to sell your company. While some of your team may share in this desire, you must keep the everyday operations moving ahead. You can bring in a consultant to help you package your company long before you begin to talk to brokers or potential suitors. If things look good, you can proceed. If not, you can keep this as a confidential alternative.

Isolate company identity
There are many times that your company identity gets in the way of your accomplishing your goals. Calling up a competitor to ask about their product will not likely result in much useful information. Calling a potential acquisition may scare that company. A consultant can isolate your identity while working in an ethical manner.
Example: You want to acquire a small company whose technology would be really useful. They simply may not be considering any such sell and if you call them, you might scare them away. Yet a consultant can talk to them and gain some trust prior to introducing your company.

Some companies are great at providing internal education on timely topics. Others simply never get started. A consultant can drive box lunch universities with topics that are of interest while building internal morale since you care enough to provide this to your team.
Example: You may want to develop a company intranet. Yet your staff has never done this. A consultant can come in and provide working knowledge through classes that will allow your team to do this task.

There are many reasons in addition to the above for using a consultant. Identifying your reasons can help you set expectations and manage the process.

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