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Like every community, our barter economy community needs a way to found and grow it. In our case, we weill start lcoally with a pilot community in Matera, southern Italy, alongside the unMonastery project. But how?
Here are our current ideas for local community development modes, excluding the pure Internet and global ones. Since we have no practical experience with community building in the team, we appreciate all input from networking and communications people which of these ideas are applicable in Southern Italy, and how. This is just an idea collection – we don’t have a plan for Matera yet, but you can help us make a plan 
- Starting from existing communities. As pointed out by Matslats from Community Forge when discussing alternative economics with him, it is better to support existing communities by providing them with tools than to start a new one. I would add, it is also more time-efficient. What communities are there in Matera who might want to add barter exchange for mutual help? Candidates are, among others, coworking spaces, weekly agro markets, hackerspaces, community gardens, collective consumption groups, ... .
- Integrate with a makerspace. This should be a nice hangout place for the young unemployed. So basically it has to be open a good part of the week, as an open access space where no membership is required (except maybe a fee in barter, which the makerspace may then use to purchase common tools from members etc.). The social dynamics of makerspaces are of course non-transactional for a start, with lots of generous free help, and this should be kept. However, when people need a lot of help with own projects, it's socially unacceptable to ask for that, and here barter exchange has its place. There should be a way how the people and resources in this makerspace can collaborate with and contribute to other projects of the unMonastery, and community projects for the city – see some proposals for that. Accidental business idea generation in this space is "allowed" :-) Some people might be able to earn a living in barter after some time of hacking away on their ideas, and that's exactly what Economy App wants to facilitate.
Hopefully, unMonastery could provide the physical space for a makerspace. Economy App would provide an initial collection of the most important tools, and people would bring in more tools and materials over time. Oh I just see that Matera has a hackerspace already. And of course there’s also Casa Netural. Nice. No need to duplicate efforts.
- Maker parties. Parties are a good way for seeding and growing a community, as proposed by Alberto where he mentions that parties are one of his fav tools of public policy ... :-) The themes would be somehow connected to the "productive fun / enjoyable work" of the barter economy as we envision it. A natural way would be having regular parties when having a makerspace anyway, something where people from Matera and farther off can gather to show their creations. This can be anything from pure fun stuff to artful things and products for daily use, and all can be offered in the barter economy software so that people can wish for them and get their own ones afterwards.
- Neighborhood parties or something? What are viable modes to connect with the immediate neighborhood of the unMonastery in the Sassi?
- Maker warehouse / brick-and-mortar barter shop. Something that, again, would well integrate with a makerspace: a showroom where (1) makerspace raw materials are for sale in barter, like defective electronics for parts etc., and (2) where people's makerspace creations are permanently shown and can be acquired via network barter, either the very objects or equivalent ones that are made to order. The same concept could be possible in a small publicly accessible brick-and-mortar shop somewhere in the city, or in the unMonastery building itself (then combined with a hangout space). A physical presence might be quite a strong invitation to get to know the network barter concept, and possible to get engaged in it. It's like a "shopping experience", just that you can "only" look around and wish for the products (by scanning a QR code with your smartphone), because they are only for barter, not for sale in money. This might be " a feature, not a bug", as it's ok to just look around, not feeling compelled to buy anything. The products, which might include a good part of unusual and creative handicraftswork like on Etsy, would be interesting to look at and to test out, and would frequently change, so people would hopefully stop by frequently.
- Community mapping. It may be that the many people like the barter economy idea, but lack the time or motivation to indeed start with it (similar to how most people know it's good to encrypt your e-mail, and still don't do it because they don't find the time to set it all up). This problem could be fixed if the platform operators or enthusiastic users visit those interested in joining, and set up their account, offers and wishes in half an hour of interviewing them. But what would be a good way (for Southern Italy) to find such interested people who need this last bit of support to join?
- Local exchange meetings as community magnet. This is an idea practiced in a direct producer-to-consumer agricultural market in Volos, Greece: they hold a bi-weekly meeting where orders are fulfilled. Doing something similar in a local barter economy would (1) fix the problem of having to trust the seller for delivery, as everyone knows they will both receive and give at the same meeting, (2) solve the delivery logistics very efficiently via a central hub and (3) would provide a nice community event that interested people can join, without committing to the barter economy yet.
- The month of barter. (This one is inspired by fellow Edgeryder @sammuirhead's Year of Open Source – look it up, it's very ... inspiring :-) The idea is to persuade a (relatively small, maybe 5-10 people) subgroup of unemployed people in an initial, larger pilot barter community to try living from barter alone for one month. Then evaluate and publish the results – if it works, it would be quite spectacular and could make it into national press. With this added publicity, repeat with larger and larger groups and for longer times. When it works out well and is published well, people might finally switch to living from barter permanently.