When you need to hold a meeting with people unable to physically meet with you, there are a large array of options.  There is phone conferencing, video conferencing, and forum software.  These are the three main options you can choose from, but within each choice, there are many different ways to go.  What you choose should be based on your requirements.  There is no reason to spend lots of money on a very complex video conferencing rig when you don’t need all the features it gives you.
            Phone conferencing is the simplest and least expensive solution.  All you need is a phone with a speaker, and a service plan that allows something like three-way calling.  This might not even be necessary, if all you have to do is talk to one other person or business.  While this solution is fairly inexpensive, it is also limited in its capabilities.  All you can do is talk to the other party, you do not have the capability to show them charts or diagrams, which in a business meeting is often necessary.
            Video conferencing is probably the best option, but there are problems with it.  Depending on the software you choose, there will be different options, but any video conference will allow you to converse with the other parties and display graphics.  The main problem with video conferencing is that it can be hardware intensive.  That is, you will need computers with a lot of power to be able to run the software.  Also, you will need a broadband internet connection, which is pretty basic these days, but by no means universal.
            There are many options with video conferencing.  Various software packages allow you to choose things such as how many users can connect to the session, the resolution of the video, which determines how sharp the graphics are, and how audio is transmitted.  Will there be one central, hand-held microphone, or will each person be equipped with a clip-on microphone?  Before you can make a decision regarding what to buy, you must list all your requirements and then see what package best matches up.
            Forum software is not for real-time communication, but is best suited for brainstorming over a long period of time.  These are web-based applications that can be run off of the company server, and can be password protected so only authorized personnel can post.  There are a great many programs available, most of which are scalable to any size.  The criteria for determining which to use should be what kind of server you have.  Personnel can post topics, and all people authorized to post in the forum can add their ideas.  This is a very useful tool for times when a real-time conference is not ideal.
           Phone conferencing has its place, but in today’s world, video conferencing is the way to go.  Features for this have been laid out above, the key is to take these general guidelines and format them for your needs.  I would also invest in forum software, because there are situations when this will be more helpful than real-time conferences or memos.  This allows personnel to stay in touch with each other, but is not as time consuming as a conference.  Each person can check in with what everyone else has been doing at their own pace, and can be working on other projects at the same time.  This will greatly increase the efficiency of your company.  There is no one-size fits all solution for your conferencing needs, but hopefully this will get you on your way to finding a solution for your particular needs.