A method of making an implantable scaffold for repairing damaged or diseased tissue includes the step of suspending pieces of an extracellular matrix material in a liquid. The extracellular matrix material and the liquid are formed into a mass. The liquid is subsequently driven off so as to form interstices in the mass. The scaffold may further comprise biological agents that promote tissue repair and healing. Porous implantable scaffolds fabricated by such a method are also disclosed.