Abstract: The turbid nature of refractive index distribution within living tissues introduces severe aberrations to light propagation thereby severely compromising image reconstruction using currently available non-invasive techniques. Numerous approaches of endoscopy, based mainly on fibre bundles or GRIN-lenses, allow imaging within extended depths of turbid tissues, however, their footprint causes profound mechanical damage to all overlying regions. Progress in the domain of complex photonics enabled a new generation of minimally invasive, high-resolution endoscopes by substitution of the Fourier-based image relays with a holographic control of light propagating through apparently randomizing multimode optical waveguides. This form of endo-microscopy became recently a very attractive way to provide minimally invasive insight into hard-to-access locations within living objects. I will review our fundamental and technological progression in this domain and introduce several applications of this concept in bio-medically relevant environments.I will present isotropic volumetric imaging modality based on light-sheet microscopy. Further, I will demonstrate the utilization of multimode fibres for imaging in a brain tissue of a living animal model. Lastly, I will show the development and exploitation of highly specialised fibre probes for numerous advanced bio-photonics applications including high-resolution imaging and optical manipulation.