3D Bioprinting is the technology that enables printing of functional living human tissues and organs. 3D bioprinting relies on the same principles as 3D printing where a construct is printed, layer by layer, from bottom to top -sometimes from top to bottom- in order to create a complete structure. While a 3D printer melts a filament to deposit a layer of a plastic, PLA for instance, a 3D bioprinter will deposit a layer of what is called a bioink, a supporting material for the cells. Two main bioprinting techniques exist today: -Firstly, a method where a dual printing technique is utilised where a first layer of supporting biopaper is printed and then a second layer of cells is deposited on top of it. Then the process is continuously repeated: biopaper, cells, biopaper, cells etc... -The second technique involves a method that Team CELLINK has been developing, where the bioink is mixed together with cells using a specifically developed mixing device, CELLMIXER. The printing is then performed through a simple one step process where a single printing head is sufficient and the cells are deposited simultaneously together with the bearing structure. Can we can print a fully functional heart? As Stuart K. Williams, Ph.D, from the university of Louisville says "It's just a pump with tubes you need to connect" but we are not there yet, it's all about the " strategic placement of the valves and big vessels", this would be achievable within a decade he asserts. However, what can be done today is the bioprinting of tissue like cartilage, skin, or liver. Such tissue can be used in drug discovery where researchers can test new potential treatments and evaluate efficacy in very early stages. This process allows us to produce more realistic and functional models of what is truly happening at the cellular level as opposed to 2D cell culturing, where cells are not expanding in a proper 3D environment. As a result, new drugs and treatments will reach clinical trials faster with a decreased number of failures and reduced need of animal testing. In cosmetology, for instance, the goal everybody is striving for is to completely eradicate the need of animal trials, which companies such as Organovo, L'Oreal, BASF, Poietis are currently working on by developing skin tissue models. One has to remember, the process of printing the actual tissue structure is a critical step, but the most essential one is the culturing of the bioprinted constructs in order to have the cells grow and proliferate. Therefore, the focus must be on the cell friendly and supporting material. Much like the typical paper printer, the magic is in the ink. Bioinks: The bioink is making the magic of 3D bioprinting happening. A cell supporting material mimicking the native tissue in terms of its structural organization and function at a microscopic and macroscopic scale. Today's research is being more and more advanced on the development of bioinks. Many universities are developing in-house bioinks, but the struggle is not in the actual making of one but in the making of a wide range of them for different tissue type with reproducibility from batch to batch. This is where the industry stands, having a standard base in order for the user to take the research to the next level by reducing inconsistencies. Much like the paper printer industry a standard will be set on the bioink allowing the research to focus on the bioprinting process itself, the culturing of the bioprinted constructs and giving cells the right nutrients the right way to actually form the finalised tissue or organ. There was a time where scientists made there own culturing solution with nutrients, growth factors etc. Nowadays, Basal Media is a product used daily by researchers, produced by the industry to allow an increase of scientific discoveries. Bioprinters 3D Bioprinters range from a couple of hundred thousand dollars to some thirty thousand dollars. The most advanced bioprinters such as RegenHU's 3D Discovery, EnvisionTEC's 3D Bioplotter, AdvancedSolution's BioAssemblyBot and Organovo's NovoGen MMX are on their way to become the machines that will allow bioprinting of fully functional organs and tissues that can then be implanted in the future. All those bioprinters offer amazing features such as very high accuracy, ability to print multiple cell types with multiple parameters simultaneously, and sustain high cell viability. These are the machines that will one day stand in the operating room printing out new organs while the patient is on the operating table, the true futuristic vision we foresee. The question is, though, what is the road map to get to that destination? Firstly, we must better understand how individual cells interact within the bioprinted tissue structure to more realistically mimic real living tissue. This process will take several years of research, going from printing of single tissue (e.g. dermis) to multiple tissue (e.g. epidermis + dermis = skin). This is why we will soon start seeing a boom of cost effective 3D bioprinters allowing these types of gradual discoveries that will take us closer and closer to the operating room. The very cost effective units will provide early researchers the possibility to discover the bioprinting field, however a growing gap will eventually start to appear in between these cost effective units and the very advanced units and there will eventually be an unmet need for bioprinters in between that can offer more precise collection of publishable data that will allow the scientific community to faster learn from each other and reduce the learning curve. Very cost effective units will be made for classroom and early stage discoveries, intermediate bioprinters will take early research to the next step of precision and advanced research, which in turn will lead to full utilization of the advanced bioprinters to ultimately save lives. We have to remember, we must learn to crawl before we can learn to walk. Team CELLINK.