A method of generating droplets, comprising: using a pumping mechanism to transport a first fluid in a first conduit; and using a pumping mechanism to transport a second fluid in a second conduit, wherein: the pumping mechanism comprises a first rotatable member having one or more radially peripheral portions that engage against the first and second conduits (2,6) to apply a dynamic deformation to the first and second conduits (2,6) on rotation of the first rotatable member, the dynamic deformation being such as to drive a pulsatile motion of the first and second fluids (4,8) in the first and second conduits (2,6), the pulsatile motions of the first and second fluids (4,8) are phase shifted relative to each other at a first junction between the first and second conduits (2,6) downstream of the pumping mechanism resulting in the formation of droplets of the second fluid in the first fluid at the first junction, and the first fluid comprises a carrier fluid and the second fluid comprises a sample fluid, the sample fluid being immiscible with the carrier fluid, characterized in that: the one or more radially peripheral portions comprises a thread winding around the axis of the first rotatable member and the phase shifting of the pulsatile motions of the first and second fluids (4,8) at the first junction is provided by positioning the first and second conduits (2,6) at different angular positions around the circumference of the first rotatable member. using a pumping mechanism to transport a first fluid in a first conduit; and using a pumping mechanism to transport a second fluid in a second conduit, wherein: the pumping mechanism comprises a first rotatable member having one or more radially peripheral portions that engage against the first and second conduits (2,6) to apply a dynamic deformation to the first and second conduits (2,6) on rotation of the first rotatable member, the dynamic deformation being such as to drive a pulsatile motion of the first and second fluids (4,8) in the first and second conduits (2,6), the pulsatile motions of the first and second fluids (4,8) are phase shifted relative to each other at a first junction between the first and second conduits (2,6) downstream of the pumping mechanism resulting in the formation of droplets of the second fluid in the first fluid at the first junction, and the first fluid comprises a carrier fluid and the second fluid comprises a sample fluid, the sample fluid being immiscible with the carrier fluid, characterized in that: the one or more radially peripheral portions comprises a thread winding around the axis of the first rotatable member and the phase shifting of the pulsatile motions of the first and second fluids (4,8) at the first junction is provided by positioning the first and second conduits (2,6) at different angular positions around the circumference of the first rotatable member. the pumping mechanism comprises a first rotatable member having one or more radially peripheral portions that engage against the first and second conduits (2,6) to apply a dynamic deformation to the first and second conduits (2,6) on rotation of the first rotatable member, the dynamic deformation being such as to drive a pulsatile motion of the first and second fluids (4,8) in the first and second conduits (2,6), the pulsatile motions of the first and second fluids (4,8) are phase shifted relative to each other at a first junction between the first and second conduits (2,6) downstream of the pumping mechanism resulting in the formation of droplets of the second fluid in the first fluid at the first junction, and the first fluid comprises a carrier fluid and the second fluid comprises a sample fluid, the sample fluid being immiscible with the carrier fluid, characterized in that: the one or more radially peripheral portions comprises a thread winding around the axis of the first rotatable member and the phase shifting of the pulsatile motions of the first and second fluids (4,8) at the first junction is provided by positioning the first and second conduits (2,6) at different angular positions around the circumference of the first rotatable member.