Packaging has evoluted for years with the sole purpose of protecting the electronics from the environment and providing a suitable operating environment. Integration became a necessity and technologies as System-in-Package emerged and enabled the integration of components built with different technologies within a single package. All this evolution lead to technologies as Wireless Sensor Networks (WSNs), networks composed of nodes which at the time contain sensors to monitor environmental variables like temperature, humidity, pressure, location, etc. in different locations at the same time. The nodes communicate the obtained data to a main location or share it with nearby nodes. WSNs are the perfect example of a technology that requires a SiP approach since it is composed by an antenna and a radio chip to provide communication skills, one or more sensors to provide sensing skills, a microcontroler to provide processing capabilities and a battery to provide electrical energy to the system. New technologies create new needs. In the areas of logistics and asset management those new needs will be created by the technology proposed in the PLEISTER (Packaged Label Electronics Including Sensing Talkative Enhanced Radio). This thesis is the product of working on low-temperature and low-cost packaging solutions for the PLEISTER project. In the vision of the PLEISTER project, a group of Wireless Sensor Network nodes can form a self-contained network capable of monitoring itself; that is to say, if a node joins/leaves the network, this will be noticed automatically and reported to other nodes. Furthermore, the network can sense and monitor status information as location, temperature, humidity, among others. In addition, the methods proposed and developed within the frame of the PLEISTER project are extended for their application on packaging solutions for microfluidics. Accelerated testing is used to test the compatibility of the different materials used within determined packaging solution and accelerate the possible failures. Failure analysis techniques are used to locate and analyse the failures. What concerns the Wireless Sensor Network nodes, the packaging solutions are developed from two points of view, the practical approach and the research approach. The practical approach uses technologies already tested and available in the market to propose a packaging solution while the research approach investigates the use of new methods to propose a packaging solution for WSN nodes. Two topics are developed during the research approach: the use of Electrically Conductive Adhesives (ECAs), as a replacement for ultrasonic welding and soldering, to electrically and mechanically attach the Li-ion batteries to the electronics, and the use of inkjet printing technology to print interconnection lines directly on top of the battery and therefore replace the substrate material by the battery. What concerns the ECAs, the contact resistance of glued bonds is higher than the contact resistance of welded bonds. When welding, the oxide layer of the material is completely removed and when gluing, the oxide layer is not totally removed due to the instant contact of the surface with oxygen prior to gluing and after removing the oxide. When low-temperatures are desired during the fabrication process and welding is not possible, gluing is a good option. If used for long time, the contacts corrode due to the presence of humidity and the composition of the joined materials (aluminum and silver) causing an increase in the contact resistance; however, biased tests prove that the increased contact resistance may not be a problem, depending on the currents required by the application. Furthermore, inkjet printing of reliable interconnection lines directly on Li-ion batteries is possible. The packaging foil from the Li-ion battery presented in this work is hydrophobic and therefore a plasma treatment is desired to improve the wettability of the surface. Silver inks present good electrical performance, the resistivity and microstructure is not affected by different ageing processes and there is no indication of silver migration; however, the adhesion can be improved and optimized according to the ink-substrate combination to be used. The application requires inks that cure at less than 155 °C; the lines must be printed before forming the battery. UV curable or room temperature curable inks are desired; in this case, the lines can be printed after forming the battery. In the second part, packaging solutions for microfluidic applications are developed. A packaging concept to integrate electronics and nano/microfluidic chips in one device is developed. For this, the use of PCB material as substrate and mechanical support for the chips is suggested. The use of TMMF dry film resist to create channels on top of the PCB material and chips is proposed. The inlaying of the chips in the PCB material is experimentally researched as well as the lamination of the microfluidic channels. Furthermore, inkjet printing is used to print electrical interconnection lines from the pads on the chip to the tracks on the PCB. Inlaying the chips in the PCB is the most critical part of the process, the chip and the PCB have to be at the same level and the space between the chip and the PCB must be controlled to ensure that the profile of the surface on which the channels and interconnection lines are fabricated, is as flat as possible. The printed lines should be printed before laminating the channels since the ink cures at 125 °C. UV inks and room temperature curing inks are desired. Laminating TMMF channels is possible, however the baking temperatures during the fabrication process need to be ramped slowly to avoid cracks in the TMMF laminated over the chips. Furthermore, since the channels are wide (more than 500 µm), the sealing of the channels has to be performed at room temperature; this causes a weak seal and thus the devices should be used carefully. The integration methods developed and researched in this thesis can be expanded to a broad range of applications.