Relation 
Entities to select 
Resulting relations 
Horizontal
or Vertical 
One or more lines or two or more points. 
The lines become horizontal or vertical (as
defined by the current sketch space). Points are aligned horizontally
or vertically. 
Collinear

Two or more lines. 
The items lie on the same infinite line. 
Coradial 
Two or more arcs. 
The items share the same centerpoint
and radius. 
Perpendicular 
Two lines. 
The two items are perpendicular to each other. 
Parallel 
Two or more lines.
A line and a plane (or a planar face) in a
3D sketch. 
The items are parallel to each other.
The line is parallel to the selected plane. 
ParallelYZ 
A line and a plane (or a planar face) in a
3D sketch. 
The line is parallel to the YZ
plane with respect to the selected plane. 
ParallelZX 
A line and a plane (or a planar face) in a
3D sketch. 
The line is parallel to the ZX
plane with respect to the selected plane. 
AlongZ 
A line and a plane (or a planar face) in a
3D sketch. 
The line is normal to the face of the selected
plane. 
Relations to the global axes are called AlongX, AlongY,
and AlongZ. Relations that are
local to a plane are called Horizontal,
Vertical, and Normal.

Tangent 
An arc, ellipse, or spline,
and a line or arc. 
The two items remain tangent. 
Concentric 
Two or more arcs, or a point and an arc. 
The arcs share the same centerpoint. 
Midpoint 
Two lines or a point and a line. 
The point remains at the midpoint of the line. 
Intersection 
Two lines and one point. 
The point remains at the intersection of the
lines. 
Coincident 
A point and a line, arc, or ellipse. 
The point lies on the line, arc, or ellipse. 
Equal 
Two or more lines or two or more arcs. 
The line lengths or radii remain equal. 
Equal Curvature 
Two splines 
The radius of curvature
and the vector (direction) matches between the two splines. 
Symmetric 
A
centerline and two points, lines, arcs, or ellipses. 
The items remain equidistant from the centerline,
on a line perpendicular to the centerline. 
Fix 
Any entity. 
The entity’s size and location are fixed.
However, the end points of a fixed line are free to move along the infinite
line that underlies it. Also, the endpoints of an arc or elliptical segment
are free to move along the underlying full circle or ellipse. 
Pierce 
A sketch point and an axis, edge, line, or
spline. 
The sketch point is coincident to where the
axis, edge, or curve pierces the sketch plane. The pierce relation is
used in Sweeps
with Guide Curves. 
Merge Points 
Two sketch points or endpoints. 
The two points are merged into a single point. 