Researchers from Brazil reached out to a researcher in the United States to co-develop and evaluate the psychometric properties of a Brazilian version of an autism stigma (social distance) scale and a Participatory Autism Knowledge-Measure (Study 1) and to assess the impact of an online training on autism stigma and knowledge in a Brazilian sample (Study 2). In a psychometric study, 532 Brazilians completed the stigma (EARPA) while 510 completed the knowledge scale (ECAT). In Study 2, 79 Brazilians (mostly white, female university students) participated in a quasi-experimental training evaluation. Exploratory graph analysis revealed one cluster on the EARPA and four clusters on the ECAT (intervention, diagnosis and etiology; autism in adulthood; repetitive behaviors and restricted interests; and socio-communicative development). The training evaluation revealed improvements across most EARPA and ECAT items, as well as changes in all centrality indicators assessed through the network analysis, suggesting that autism stigma and knowledge improved with training. Both scales are promising instruments and may be useful in future Brazilian and cross-cultural studies. The training could be used more widely to improve autism understanding in Brazil. Further cultural adaptations will likely be needed to make the training well-suited to the myriad cultural contexts present within Brazil.