An infusion device (10, 100, 120, 140, 160, 180, 200, 270, 280), comprising: a hub, comprising a skin adhesion surface and a skin adhesion surface opening; and a catheter body (14, 14a, 14b, 14c, 14d, 14e, 14f, 64, 84, 134, 152, 166, 192, 202, 252, 260, 272, 274) extending between distal and proximal ends, and an axial opening passing through at least a portion of said catheter body, wherein said catheter body comprises a flexible body portion for moveably coupling a first rigid body portion to a second rigid body portion, and said second rigid body portion for coupling said flexible body portion of the catheter body to said hub through said skin adhesion surface opening, said opening surrounded by said skin adhesion surface characterized in that said catheter body comprises said first rigid body portion at said distal end, said second rigid body portion at said proximal end, and said flexible body portion therebetween, wherein at least said first rigid body portion and said flexible body portion are configured for disposal below a skin surface during use and further comprising: a union element at said proximal end of said catheter body (14, 14a, 14b, 14c, 14d, 14e, 14f, 64, 84, 134, 152, 166, 192, 202, 252, 260, 272, 274), wherein said union element is configured for disposal above a skin surface during use and configured to flexibly couple said proximal end of said catheter body with said hub, wherein said union element comprises at least one of: a ball element, wherein said ball element is configured to be rotatably captured within said hub to provide said flexible union; a sliding plate, wherein said sliding plate is configured to be slidably captured within said hub to provide said flexible union; a flexible bushing, wherein said flexible bushing is configured to be captured within said hub to provide said flexible union; and a bellows joint, wherein said bellows joint is configured to be secured to said hub to provide said flexible union; wherein said flexible union element at said proximal end of said catheter body further comprises at least one sealing element (72, 96) disposed between said catheter body and said hub. a hub, comprising a skin adhesion surface and a skin adhesion surface opening; and a catheter body (14, 14a, 14b, 14c, 14d, 14e, 14f, 64, 84, 134, 152, 166, 192, 202, 252, 260, 272, 274) extending between distal and proximal ends, and an axial opening passing through at least a portion of said catheter body, wherein said catheter body comprises a flexible body portion for moveably coupling a first rigid body portion to a second rigid body portion, and said second rigid body portion for coupling said flexible body portion of the catheter body to said hub through said skin adhesion surface opening, said opening surrounded by said skin adhesion surface characterized in that said catheter body comprises said first rigid body portion at said distal end, said second rigid body portion at said proximal end, and said flexible body portion therebetween, wherein at least said first rigid body portion and said flexible body portion are configured for disposal below a skin surface during use and further comprising: a union element at said proximal end of said catheter body (14, 14a, 14b, 14c, 14d, 14e, 14f, 64, 84, 134, 152, 166, 192, 202, 252, 260, 272, 274), wherein said union element is configured for disposal above a skin surface during use and configured to flexibly couple said proximal end of said catheter body with said hub, wherein said union element comprises at least one of: a ball element, wherein said ball element is configured to be rotatably captured within said hub to provide said flexible union; a sliding plate, wherein said sliding plate is configured to be slidably captured within said hub to provide said flexible union; a flexible bushing, wherein said flexible bushing is configured to be captured within said hub to provide said flexible union; and a bellows joint, wherein said bellows joint is configured to be secured to said hub to provide said flexible union; wherein said flexible union element at said proximal end of said catheter body further comprises at least one sealing element (72, 96) disposed between said catheter body and said hub. a ball element, wherein said ball element is configured to be rotatably captured within said hub to provide said flexible union; a sliding plate, wherein said sliding plate is configured to be slidably captured within said hub to provide said flexible union; a flexible bushing, wherein said flexible bushing is configured to be captured within said hub to provide said flexible union; and a bellows joint, wherein said bellows joint is configured to be secured to said hub to provide said flexible union; wherein said flexible union element at said proximal end of said catheter body further comprises at least one sealing element (72, 96) disposed between said catheter body and said hub.