The place of Eucharistic reservation is one of the hottest post-conciliar flashpoints for Catholics, lay and clergy alike. Previously, most North American parishes reserved the Eucharist on the main altar. The recommendation for a separate place has not been well-received in all circles, and today, there is something of a retrenchment.
The GIHCWEOM is pretty clear about the preeminent place not necessarily being preeminent during Mass. Busy churches are urged to consider the various needs of those praying, and those celebrating other sacraments. This section doesn’t touch upon the other frequent use of a church: musical and other rehearsals.
9. The place for the reservation of the eucharist should be truly preeminent. It is highly recommended that the place be suitable also for private adoration and prayer so that the faithful may readily and fruitfully continue to honor the Lord, present in the sacrament, through personal worship.
This will be achieved more easily if the chapel is separate from the body of the church, especially in churches where marriages and funerals are celebrated frequently and in churches where there are many visitors because of pilgrimages or the artistic and historical treasures.
Does your parish’s tabernacle fit the bill?
10. The holy eucharist is to be reserved in a solid tabernacle. It must be opaque and unbreakable. Ordinarily there should be only one tabernacle in a church; this may be placed on an altar or if not on an altar, at the discretion of the local Ordinary, in some other noble and properly ornamented part of the church.[Eucharisticum Mysterium 52-53]
… and its security?
The key to the tabernacle where the eucharist is reserved must be kept most carefully by the priest in charge of the church or oratory or by a special minister who has received the faculty to give communion.
Our parish’s tabernacle has an interior veil. We use option one: an oil lamp. Anybody wish to report other good options they’ve used or seen?
11. The presence of the eucharist in the tabernacle is to be shown by a veil or in another suitable way determined by the competent authority.
According to traditional usage, an oil lamp or lamp with a wax candle is to burn constantly near the tabernacle as a sign of the honor shown to the Lord.[Eucharisticum Mysterium 57]
Catholic Sensibility 
This was in the bulletin of a nearby parish this weekend. The author is the pastor and is a respected liturgist:
Treasures from the Tradition
Not until the thirteenth century do we find a mention
in historical records of a locked tabernacle. There’s
some evidence for eucharistic towers also, but often
these were in an obscure corner of the church, or even
in the off-limits sacristy. Many of us grew up “making
visits” to Jesus in the Blessed Sacrament, but it’s clear
this would raise some medieval eyebrows in confusion!
To the present day, the Eucharist is always reserved
only in a side chapel in cathedrals. The principal
focus in a cathedral is always on the altar, symbol
of Christ, and on the cathedra, symbol of the pastoral
ministry of the bishop.
In your parish church there is probably a “sanctuary
lamp,” a permanently lit candle or oil lamp indicating
the presence of the Blessed Sacrament. Sometimes it’s
in a red glass, not for any particular reason except
that it’s easy to find. There is a story of a bishop missioned
to Papua New Guinea who was distressed to
find no sanctuary lamps burning in his new diocese.
The people patiently explained that their churches
were woven of grass, and that they decided to place a
chief’s standard, a trident, in front of the tabernacle.
That was a sign in their culture that the “chief” was at
home, like raising the flag over Buckingham Palace.
The bishop, an Irish import, didn’t appreciate the
British reference, so he ordered the candles back. The
first church to burn to the ground was the cathedral,
and after two more catastrophic fires, the chief’s tridents
returned!
Rev. James Field, (c) Copyright, J. S. Paluch Co.
I find it interesting that Fr Field omitted to reference to the longstanding (like almost 1000 years) precursor to the tabernacle – the eucharistic dove, which dates to the time of the Catacombs and which, by its construction, did not require locking because it was suspended under the ciborium/baldachino over the main altar. The reservation of the Eucharist in a vessel in a prominent place in the sanctuary is much older than the advent of Eucharistic devotion in the high Middle Ages. Some liturgical designers in recent years have experimented with the resurrection of the dove, IIRC.
Btw, the longstanding reason the Eucharistic chapel has customarily been separate in cathedrals has to do with the ritual requirements of the preconciliar pontifical Mass.
In current practice, while there is ongoing argument about whether that situation of the tabernacle on the principal longitudinal axis is the optimal placement (I am agnostic on that point, other than to say that I don’t think it’s a placement that requires “fixing”), there is another and larger argument about what “truly preeminent” should like like and whether it has tended in some places to be honored in the breach.
This was in the bulletin of a nearby parish this weekend. The author is the pastor and is a respected liturgist:
Who is the pastor, Anne? Do you have a link to the bulletin in question?
In view of the tabernacle’s place in Jewish history, would not a tent-like structure behind the altar with a “temple veil” to be closed during the eucharistic liturgy, be especially effective and appropriate? It immediately suggests our linkage to Judaism, and perfectly symbolizes a “holy of holies”. The veiling during Mass serves to concentrate one’s attention on the altar and the Mass itself. With the drawn veil for private devotion outside Mass.
I saw such a veiled tent once with a seven branch candelabrum in front of it. It contained small golden oil lamps.
Beautiful golden angels were engraved along the sides of the eucharistic tent. Very impressive!
An alternative treatment might be seven golden lamps hanging before the altar in front of the veil. This could be another way of visually linking this tent-tabernacle to the altar itself.
The hanging lamps also bring to the worshipper’s mind the seven golden lamps contained in the Heavenly Banquet described in St. John’s dream contained in the Book of Revelation.