Barbara Palvin, the Hungarian model and actress, has been associated with various fashion campaigns and brands.

However, I don't have specific details about her involvement in the Lancaster Paris campaign for Spring/Summer.

Barbara Palvin has been featured in numerous high-profile fashion campaigns and has walked the runway for prestigious fashion houses.

Her collaboration with different brands often showcases her elegance, beauty, and style, aligning with the brand's aesthetic and vision.

For the most recent updates or information regarding Barbara Palvin's involvement in the Lancaster Paris Campaign for Spring/Summer or any other fashion campaigns.

I recommend checking fashion magazines, official brand announcements, or Barbara Palvin's social media accounts, where she might share updates about her modeling projects and campaigns.