A pilot valve assembly for use on a pressure regulator, the pilot valve assembly comprising: a manifold with an internal flow network; and flow controls connected to the internal flow network to permit fluid to flow amongst them, the flow controls comprising: a fixed pressure pilot valve having a fixed differential pressure; a first adjustable pilot valve configured to adjust differential pressure thereacross; and an adjustable restrictor; characterized in that the internal flow network connects an outlet of the fixed pressure pilot valve to an inlet of the first adjustable pilot valve; and the pilot valve assembly is modular and the manifold comprises a plurality of blocks (168, 170, 172) separable from one another, each block having part of the internal flow network comprising machined bores that permit flow among the flow controls (186, 188, 180); the pilot valve assembly comprising a first terminal at a particular one of the modular blocks to couple the manifold to pressure at a supply side of the pressure regulator and a second and a third terminal at another one of the modular blocks to couple the 20 manifold respectively to the outlet pressure of the pressure regulator and to a control pressure within a chamber of the pressure regulator. a manifold with an internal flow network; and flow controls connected to the internal flow network to permit fluid to flow amongst them, the flow controls comprising: a fixed pressure pilot valve having a fixed differential pressure; a first adjustable pilot valve configured to adjust differential pressure thereacross; and an adjustable restrictor; characterized in that the internal flow network connects an outlet of the fixed pressure pilot valve to an inlet of the first adjustable pilot valve; and the pilot valve assembly is modular and the manifold comprises a plurality of blocks (168, 170, 172) separable from one another, each block having part of the internal flow network comprising machined bores that permit flow among the flow controls (186, 188, 180); the pilot valve assembly comprising a first terminal at a particular one of the modular blocks to couple the manifold to pressure at a supply side of the pressure regulator and a second and a third terminal at another one of the modular blocks to couple the 20 manifold respectively to the outlet pressure of the pressure regulator and to a control pressure within a chamber of the pressure regulator. a fixed pressure pilot valve having a fixed differential pressure; a first adjustable pilot valve configured to adjust differential pressure thereacross; and an adjustable restrictor; characterized in that the internal flow network connects an outlet of the fixed pressure pilot valve to an inlet of the first adjustable pilot valve; and the pilot valve assembly is modular and the manifold comprises a plurality of blocks (168, 170, 172) separable from one another, each block having part of the internal flow network comprising machined bores that permit flow among the flow controls (186, 188, 180); the pilot valve assembly comprising a first terminal at a particular one of the modular blocks to couple the manifold to pressure at a supply side of the pressure regulator and a second and a third terminal at another one of the modular blocks to couple the 20 manifold respectively to the outlet pressure of the pressure regulator and to a control pressure within a chamber of the pressure regulator.