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    <p>In layman terms - A Manager would have many Projects, each Project would have many Workers. Right? If so:</p> <pre><code>class Project &lt; ActiveRecord::Base belongs_to :manager, :class_name =&gt; 'Employee', :foreign_key =&gt; 'manager_id' has_many :employees end class Employee &lt; ActiveRecord::Base belongs_to :project has_many :managed_projects, :class_name =&gt; 'Project', foreign_key =&gt; 'manager_id' scope :managers, includes(:managed_projects).where('manager_id IS NOT NULL).order('NAME ASC') end </code></pre> <p>This would allow Employees to be both Managers and Workers in Projects simultaneously (say for multi-tiered projects).</p> <pre><code>#The projects of the first manager (managers sorted by name) Employee.managers.first.project # The workers (Employees) working on the project with id 1 Project.find(1).workers # The manager (Employee) of the project with id 1 Project.find(1).manager #Employees that are both Workers and Managers (left as an exercise) Employee.workers_and_managers </code></pre> <p>Another way of attempting the relation is to use STI (single table inheritance), where a field names 'type' would determine if an Employee is either a Worker or a Manager (mutually exclusive)</p> <pre><code>class Employee &lt; ActiveRecord::Base #table Employees includes 'type' field end class Worker &lt; Employee belongs_to :project end class Manager &lt; Employee has_many :projects end </code></pre> <p>Now - you can do:</p> <pre><code>Manager.create(:name =&gt; 'John Doe') #you don't have to specify type - Rails will take care of it #Find Projects managed by Employee with id 1 Manager.find(1).projects #Find the project the Employee with id 2 is working on Worker.find(2).project #Find the manager of Project with id 1 Project.find(1).manager #Find workers of Project with id 1 Project.find(1).worker </code></pre>
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    1. COSo for the STI, would I define Projects as `belongs_to :manager, :foreign_key => "manager_id" \n has_many :workers, :through => :worker_shift` ? Assuming I have a separate WorkerShift model and the hmt association is defined in the Worker subclass.
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    2. COActually nevermind. Managers and Workers shouldn't be mutually exclusive, so I'll just use that first method. Thanks!
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