The equiatomic intermetallic phases CaAgIn [a = 482.75 (7), b = 750.0(1), c = 835.5(1) pm], SrAgIn [a = 495.86(5), b = 794.71(9), c = 851.89(9) pm], LaAgIn [a = 489.99(5), b = 767.93(9), c = 837.53(9) pm], and EuAgIn [a = 493.02(7), b = 781.6(1), c = 844.2(1) pm] were synthesized from the elements in sealed niobum containers. They crystallize with the EuAuGe type structure, space group Imm2. The four structures were refined from single-crystal Xray data. The silver and indium atoms build up orthorhombically dis-* Prof. Dr. R. Pöttgen 883 torted, puckered Ag 3 In 3 hexagons, which are stacked in AAЈ sequence, leading to direct Ag-Ag and In-In interlayer bonding (e.g. 303 and 304 pm in CaAgIn). Temperature dependent magnetic susceptibility measurements show a magnetic moment of 7.40(1) μ B per europium atom. EuAgIn orders antiferromagnetically at 5.7(5) K. The divalent nature of europium is also evident from 151 Eu Mössbauer spectra: δ = -10.50(1) mm·s -1 at 78 K. structures), whereas the remaining REAgIn phases show modulated structures that retain hexagonal symmetry.Herein we report on the synthesis, structures, and properties of LaAgIn and EuAgIn and the isotypic alkaline earth indides CaAgIn and SrAgIn.