Hey JoAnn Here is part of a list I use at our initial design meetings. I think Gary Ferrari gave this to me. - Gary are you still lurking on this list? 1) DESIGN REVIEW Determine performance class ( IPC 1, 2, or 3) Electrical Considerations Voltage min/max Current min/max Conductor resistance and temperature rise High frequency circuits Shielding (EMI) requirements Division between analog and digital circuits Board Dimensions Length Width Shape Thickness Copper weight ( current-carrying capacity) Component Dimensions SMD thru-hole or mix Height (including lead protrusion) Hole sizes Feasibility study Total board area required Track width Spacing Number of layers Component Placement Connectors Switches Special case parts Define component to edge spacing Routing Determine critical nets Heat dissipation/tolerance requirements Shock/vibration requirements Board retaining/extraction Fabrication/manufacturing considerations Board house capabilities Plating requirements (gold/silver/tin) Solder mask type Delivery requirements Component spacing (auto insertion?) Testing Test requirements Test point locations I'll work at getting this up (with more details) on my web site. anyone want to add to this, send e-mail to me, not the list.......... [log in to unmask] Larry Machak Saminco Inc.