I have a WPF appliction that uses WCF services to make calls to the server.

I use this property in my code to access the service

private static IProjectWcfService ProjectService
{
    get
    {
        _projectServiceFactory = new ProjectWcfServiceFactory();
        return _projectServiceFactory.Create();
    }
}

The Create on the factory looks like this

    public IProjectWcfService Create()
    {
        _serviceClient = new ProjectWcfServiceClient();

        //ToDo: Need some way of saving username and password 
        _serviceClient.ClientCredentials.UserName.UserName = "Brendan";
        _serviceClient.ClientCredentials.UserName.Password = "password";

        return _serviceClient;
    }

To access the service methods I use somethingn like the following.

ProjectService.Save(dto);

Is this a good approach for what I am trying to do? I am getting an errorthat I can't track down that I think may be realted to having too many service client connections open (is this possible?) notice I never close the service client or reuse it.

What would the best practice for WCF service client's be for WPF calling?

Thanks in advance...